 <!--1--><SECTION sectiontitle='Relaxation' tag='1'>
 <!--2--><CHOICE instruction='Which kind of relaxation do you wish to perform ?' tag='2'>
 <!--3--><DECISION description='optimize the atomic positions only' tag='3'>
 <!--4--><MOUSEENTRY instruction='Choose the technique used to optimize the atomic positions (ionmov)' tag='4'>
 <!--5--><OPTION description='molecular dynamics with optional viscous damping' variablename='ionmov' variablevalue='1' tag='5'/>
 <!--6--><OPTION description='conjugate gradient algorithm for simultaneous optimization of potential and ionic degrees of freedom' variablename='ionmov' variablevalue='4' tag='6'/>
 <!--7--><OPTION description='simple relaxation of ionic positions according to (converged) forces' variablename='ionmov' variablevalue='5' tag='7'/>
 <!--8--><OPTION description='molecular dynamics using the Verlet algorithm' variablename='ionmov' variablevalue='6' tag='8'/>
 <!--9--><OPTION description='quenched molecular dynamics using the Verlet algorithm' variablename='ionmov' variablevalue='7' tag='9'/>
<!--10--><OPTION description='molecular dynamics with Nose-Hoover thermostat, using the Verlet algorithm' variablename='ionmov' variablevalue='8' tag='10'/>
<!--11--><OPTION description='Langevin molecular dynamics' variablename='ionmov' variablevalue='9' tag='11'/>
<!--12--><OPTION description='isokinetic ensemble molecular dynamics' variablename='ionmov' variablevalue='12' tag='12'/>
         </MOUSEENTRY>
         </DECISION>
<!--13--><DECISION description='optimize the atomic positions as well as the cell geometry' tag='13'>
<!--14--><MOUSEENTRY instruction='Choose the technique used to optimize the atmic positions (ionmov)' tag='14'>
<!--15--><OPTION description='structural optimization using the Broyden-Fletcher-Goldfarb-Shanno minimization (BFGS)' variablename='ionmov' variablevalue='2' tag='15'/>
<!--16--><OPTION description='BFGS minimization, modified to take into account the total energy as well as the gradients (as in usual BFGS)' variablename='ionmov' variablevalue='3' tag='16'/>
         </MOUSEENTRY>
<!--17--><MOUSEENTRY instruction='Choose the technique used to optimize the geometry of the unit cell (optcell)' tag='17'>
<!--18--><OPTION description='optimisation of volume only (rprim unchanged ; homogenous dilatation of acell)' variablename='optcell' variablevalue='1' tag='18'/>
<!--19--><OPTION description='full optimization of cell geometry (modify rprim and acell)' variablename='optcell' variablevalue='2' tag='19'/>
<!--20--><OPTION description='constant-volume optimization of cell geometry (modify acell and rprim under constant volume constraint)' variablename='optcell' variablevalue='3' tag='20'/>
<!--21--><OPTION description='optimize acell(1) while keeping acell(2) and acell(3) unchanged (only works if acell(1) is orthogonal to acell(2) and acell(3))' variablename='optcell' variablevalue='4' tag='21'/>
<!--22--><OPTION description='optimize acell(2) while keeping acell(1) and acell(3) unchanged (only works if acell(2) is orthogonal to acell(1) and acell(3))' variablename='optcell' variablevalue='5' tag='22'/>
<!--23--><OPTION description='optimize acell(3) while keeping acell(1) and acell(2) unchanged (only works if acell(3) is orthogonal to acell(1) and acell(2))' variablename='optcell' variablevalue='6' tag='23'/>
<!--24--><OPTION description='optimize acell(2) and acell(3) while keeping acell(1) unchanged (only works if acell(1) is orthogonal to acell(2) and acell(3))' variablename='optcell' variablevalue='7' tag='24'/>
<!--25--><OPTION description='optimize acell(1) and acell(3) while keeping acell(2) unchanged (only works if acell(2) is orthogonal to acell(1) and acell(3))' variablename='optcell' variablevalue='8' tag='25'/>
<!--26--><OPTION description='optimize acell(1) and acell(2) while keeping acell(3) unchanged (only works if acell(3) is orthogonal to acell(1) and acell(2))' variablename='optcell' variablevalue='9' tag='26'/>
         </MOUSEENTRY>
<!--27--><KEYBOARDENTRY instruction='Enter the maximal permitted scaling of the lattice parameters during the cell optimization (dilatmx)'	variablename='dilatmx' textlen='1' tag='27'/>
<!--28--><KEYBOARDENTRY instruction='Enter the energy cutoff smearing (ecutsm) (recommended value : 0.5 Ha)' variablename='ecutsm' textlen='1' tag='28'/>
         </DECISION>
<!--29--><KEYBOARDENTRY instruction='Enter the  maximal absolute force tolerance (in hartree/bohr) below which BFGS structural relaxation iterations will stop (tolmxf)' variablename='tolmxf' textlen='1' tag='29'/>
<!--30--><KEYBOARDENTRY instruction='Enter the maximum number of structural optimization steps over which calculation will automatically stop (ntime)' variablename='ntime' textlen='1' tag='30'/>
         </CHOICE>
         </SECTION>
