Dear all, Are 'md' calculations compatible with constraints in 4.3.2 ?
The following error occurs : "constraints only with damped dynamics and fixed cell" (in acetylene.out attached) with qe-4.3.2, following the nice hands-on tutorial, relaxation part, at http://www.fisica.uniud.it/~giannozz/QE-Tutorial/ using the modified input acetylene-SHAKE_mod.in (attached) (modified because the format seems to have changed a little since the writing of the tutorial) But the INPUT_PW.html says that CONSTRAINTS is an "Optional card, used for constrained dynamics or constrained optimisations (only if ion_dynamics='damp' or 'verlet', variable-cell excepted)" This is also supported by CASE ( calculation = 'md' ) 'verlet' : (default) use Verlet algorithm to integrate Newton's equation. For constrained dynamics, see CONSTRAINTS card So constraints should work with md and verlet ? but in PW/input.f90 there is, line 1436 : IF ( lconstrain ) THEN IF ( .NOT. ldamped .OR. lmovecell ) CALL errore( 'iosys', & 'constraints only with damped dynamics and fixed cell', 1 ) which seems to forbid constraints with verlet ? (This has been introduced in Revision 7099 ) Note: changing 'verlet' to 'langevin' yields the same error, And actually ldamped is not defined for 'md' calculations (ibid, lines 372-393) Should 'md' calculations really work with constraints or not ? Or am I missing anything ? Best regards, Jean-Roch Huntzinger -- L2C/SMC UMR 5221 - Universit? Montpellier 2, CNRS case courrier 074 34095 Montpellier cedex 5 tel: 04 67 14 41 38 fax: 04 67 14 37 60 -------------- next part -------------- &CONTROL calculation = 'md' , restart_mode = 'restart' , pseudo_dir = './' , nstep = 50 , dt = 10.D0 , / &SYSTEM ibrav = 1, celldm(1) = 10.D0, nat = 4, ntyp = 2, ecutwfc = 24.0D0 , ecutrho = 144.0D0 , nosym = .true. , occupations = 'smearing' , degauss = 0.01D0 , smearing = 'gaussian' , / &ELECTRONS conv_thr = 1.D-7 , mixing_beta = 0.5D0 , / &IONS ion_dynamics = 'verlet' , pot_extrapolation = 'second_order' , wfc_extrapolation = 'second_order' , / ATOMIC_SPECIES H 1.00000 H.US_PBE.RRKJ3.UPF C 12.00000 C.US_PBE.RRKJ3.UPF ATOMIC_POSITIONS bohr C 0.000000000 0.000000000 0.000000000 0 0 0 C 2.100000000 0.000000000 0.000000000 H -1.600000000 0.400000000 0.000000000 H 3.600000000 -0.400000000 0.000000000 K_POINTS gamma CONSTRAINTS 3 1e-8 'planar_angle' 1 2 4 'distance' 1 3 'distance' 2 4 -------------- next part -------------- Program PWSCF v.4.3.2 starts on 8Jan2012 at 2:15:46 This program is part of the open-source Quantum ESPRESSO suite for quantum simulation of materials; please cite "P. Giannozzi et al., J. Phys.:Condens. Matter 21 395502 (2009); URL http://www.quantum-espresso.org";, in publications or presentations arising from this work. More details at http://www.quantum-espresso.org/wiki/index.php/Citing_Quantum-ESPRESSO Current dimensions of program PWSCF are: Max number of different atomic species (ntypx) = 10 Max number of k-points (npk) = 40000 Max angular momentum in pseudopotentials (lmaxx) = 3 Waiting for input... Reading input from stdin Reading 3 constraints; tolerance: 0.000000 1) planar angle between atoms: 1 2 4 2) distance between atoms: 1 3 3) distance between atoms: 2 4 file H.US_PBE.RRKJ3.UPF: wavefunction(s) 1S renormalized file C.US_PBE.RRKJ3.UPF: wavefunction(s) 2S 2P renormalized %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% from iosys : error # 1 constraints only with damped dynamics and fixed cell %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% stopping ...
