<?xml version="1.0" ?>
<Heff_definition>
  <coefficient number="1" value="  -0.8120713995E-01" text="(Ti_y-O1_y)^2(Ti_y-O1_y[1 1 0])^1(eta_1)^1">
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 1 0</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 1"/>
    </term>
    <term weight="-1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 0</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 1 0</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 1"/>
    </term>
    <term weight="-1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 1 0</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 2"/>
    </term>
    <term weight="-1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 0</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 2"/>
    </term>
    <term weight="-1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 -1 0</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 1</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 2"/>
    </term>
    <term weight="-1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 0</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 2"/>
    </term>
    <term weight="-1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 1</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 1</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 1"/>
    </term>
    <term weight="-1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 0</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 1</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 1"/>
    </term>
    <term weight="-1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 1</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 3"/>
    </term>
    <term weight="-1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 -1</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 3"/>
    </term>
    <term weight="-1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 3"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 -1</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 3"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 1</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 3"/>
    </term>
    <term weight="-1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 -1</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 3"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 -1</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 3"/>
    </term>
    <term weight="-1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="1">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <strain power=" 1" voigt=" 3"/>
    </term>
  </coefficient>
  <coefficient number="2" value="   0.2348990031E+01" text="(Ti_y-O1_y)^6">
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
    </term>
  </coefficient>
  <coefficient number="3" value="   0.1689010498E-01" text="(Ti_y-O1_y[1 1 0])^6">
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 -1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 -1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 -1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 -1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 -1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="6">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
    </term>
  </coefficient>
  <coefficient number="4" value="   0.7547891673E-01" text="(Ti_y-O1_y)^4(Ti_y-O1_y[1 1 0])^2">
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 -1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 -1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 -1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 -1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 -1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
    </term>
  </coefficient>
  <coefficient number="5" value="   0.2686815417E-01" text="(Ti_y-O1_y)^2(Ti_y-O1_y[1 1 0])^4">
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 -1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 -1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 -1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 -1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 -1</cell_b>
      </displacement_diff>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="4">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
    </term>
  </coefficient>
  <coefficient number="6" value="   0.4583702314E+01" text="(Ti_y-O1_y)^2(Ti_y-O1_y[1 1 0])^2(eta_1)^2">
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 1 0</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 0</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 1 0</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 1 0</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 0</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 -1 0</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 1</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 0</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 -1 1</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 1</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 0</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>-1 0 1</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="4" direction="z" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 1</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 3"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 -1</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 3"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 3"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="3" direction="x" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>1 0 -1</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 3"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 1</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 3"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 -1</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 3"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 -1</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 3"/>
    </term>
    <term weight=" 1.000000">
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 1 0</cell_b>
      </displacement_diff>
      <displacement_diff atom_a="1" atom_b="2" direction="y" power="2">
        <cell_a>0 0 0</cell_a>
        <cell_b>0 0 1</cell_b>
      </displacement_diff>
      <strain power=" 2" voigt=" 3"/>
    </term>
  </coefficient>
  <coefficient number="7" value="   0.1000000000E+07" text="(eta_1)^6">
    <term weight=" 1.000000">
      <strain power=" 6" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 6" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 6" voigt=" 3"/>
    </term>
  </coefficient>
  <coefficient number="8" value="   0.1000000000E+07" text="(eta_1)^4(eta_2)^2">
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 1"/>
      <strain power=" 2" voigt=" 2"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 2"/>
      <strain power=" 2" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 2"/>
      <strain power=" 2" voigt=" 3"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 1"/>
      <strain power=" 2" voigt=" 3"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 3"/>
      <strain power=" 2" voigt=" 1"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 3"/>
      <strain power=" 2" voigt=" 2"/>
    </term>
  </coefficient>
  <coefficient number="9" value="   0.1000000000E+07" text="(eta_1)^4(eta_4)^2">
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 1"/>
      <strain power=" 2" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 2"/>
      <strain power=" 2" voigt=" 5"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 3"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
  </coefficient>
  <coefficient number="10" value="   0.1000000000E+07" text="(eta_1)^4(eta_5)^2">
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 1"/>
      <strain power=" 2" voigt=" 5"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 2"/>
      <strain power=" 2" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 2"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 1"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 3"/>
      <strain power=" 2" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 3"/>
      <strain power=" 2" voigt=" 5"/>
    </term>
  </coefficient>
  <coefficient number="11" value="   0.1000000000E+07" text="(eta_1)^2(eta_2)^2(eta_3)^2">
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 2" voigt=" 3"/>
    </term>
  </coefficient>
  <coefficient number="12" value="   0.1000000000E+07" text="(eta_1)^2(eta_2)^2(eta_4)^2">
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 2" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 2" voigt=" 5"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 2" voigt=" 3"/>
      <strain power=" 2" voigt=" 5"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 2" voigt=" 3"/>
      <strain power=" 2" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 3"/>
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 3"/>
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
  </coefficient>
  <coefficient number="13" value="   0.1000000000E+07" text="(eta_1)^2(eta_2)^2(eta_6)^2">
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 2" voigt=" 3"/>
      <strain power=" 2" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 2" voigt=" 3"/>
      <strain power=" 2" voigt=" 5"/>
    </term>
  </coefficient>
  <coefficient number="14" value="   0.1000000000E+07" text="(eta_1)^2(eta_4)^4">
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 4" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 4" voigt=" 5"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 3"/>
      <strain power=" 4" voigt=" 6"/>
    </term>
  </coefficient>
  <coefficient number="15" value="   0.1000000000E+07" text="(eta_1)^2(eta_4)^2(eta_5)^2">
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 2" voigt=" 4"/>
      <strain power=" 2" voigt=" 5"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 2" voigt=" 5"/>
      <strain power=" 2" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 2" voigt=" 5"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 2" voigt=" 4"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 3"/>
      <strain power=" 2" voigt=" 6"/>
      <strain power=" 2" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 3"/>
      <strain power=" 2" voigt=" 6"/>
      <strain power=" 2" voigt=" 5"/>
    </term>
  </coefficient>
  <coefficient number="16" value="   0.1000000000E+07" text="(eta_1)^2(eta_5)^4">
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 4" voigt=" 5"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 4" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 4" voigt=" 6"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 4" voigt=" 6"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 3"/>
      <strain power=" 4" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 3"/>
      <strain power=" 4" voigt=" 5"/>
    </term>
  </coefficient>
  <coefficient number="17" value="   0.1000000000E+07" text="(eta_1)^2(eta_5)^2(eta_6)^2">
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 1"/>
      <strain power=" 2" voigt=" 5"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 2"/>
      <strain power=" 2" voigt=" 4"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 3"/>
      <strain power=" 2" voigt=" 4"/>
      <strain power=" 2" voigt=" 5"/>
    </term>
  </coefficient>
  <coefficient number="18" value="   0.1000000000E+07" text="(eta_4)^6">
    <term weight=" 1.000000">
      <strain power=" 6" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 6" voigt=" 5"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 6" voigt=" 6"/>
    </term>
  </coefficient>
  <coefficient number="19" value="   0.1000000000E+07" text="(eta_4)^4(eta_5)^2">
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 4"/>
      <strain power=" 2" voigt=" 5"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 5"/>
      <strain power=" 2" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 5"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 4"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 6"/>
      <strain power=" 2" voigt=" 4"/>
    </term>
    <term weight=" 1.000000">
      <strain power=" 4" voigt=" 6"/>
      <strain power=" 2" voigt=" 5"/>
    </term>
  </coefficient>
  <coefficient number="20" value="   0.1000000000E+07" text="(eta_4)^2(eta_5)^2(eta_6)^2">
    <term weight=" 1.000000">
      <strain power=" 2" voigt=" 4"/>
      <strain power=" 2" voigt=" 5"/>
      <strain power=" 2" voigt=" 6"/>
    </term>
  </coefficient>
</Heff_definition>
