Molcas Forum

lijingbai2009

Member

Registered: 2019-08-28

Posts: 29

I got different velocities after reading in velocity.xyz

Hi,

I'm very curious about the read-in mechanics of &Dynamix with velo=2. My velocity.xyz is generated by dynamixtool.py:

           -0.0064753264476215           -0.0035343948628825            0.0026519639022068
            0.0101618075467630            0.0019791988180419           -0.0128164364697772
           -0.0052492439173797            0.0029287099518049            0.0067307645867850
           -0.0086878512967238            0.0172488759672971           -0.0056065125680443
            0.0110479175426015           -0.0010556319213093            0.0091191308195287
            0.0073117365710946           -0.0089948027871550            0.0073080063056633
            0.0681491511015572           -0.0909513107446637           -0.0925445752172973
           -0.0536660491205017           -0.0519481547757118           -0.0429232240467605
           -0.0364509683154225            0.0752172733769959           -0.0536279630964482
            0.0525315101242502            0.0653430240018373           -0.1020843636423861
           -0.0445245252246329            0.0729523341264425            0.0010697686155930
            0.0768097136403225           -0.0345684896850084            0.0340684631887962
           -0.0030302234651332            0.0095952510555667            0.0058350784844979
           -0.0770619701797470           -0.0478716352273786            0.0391889259861889
           -0.0051581312759038           -0.0125806095784622           -0.0055343209672818
            0.0174730759704139           -0.2177893537169123           -0.0991203319940288

The output said velocities were read in but the table gave different numbers.

     The initial mass weighted velocities (bohr/au) are read in.



       Velocities      (time	  0.0 a.u.):
 ----------------------------------------------
      No.  Atom    X          Y          Z
 ----------------------------------------------
         1  C  -0.000044  -0.000024   0.000018
         2  C   0.000069   0.000013  -0.000087
         3  C  -0.000035   0.000020   0.000046
         4  C  -0.000059   0.000117  -0.000038
         5  C   0.000075  -0.000007   0.000062
         6  C   0.000049  -0.000061   0.000049
         7  H   0.001590  -0.002122  -0.002159
         8  H  -0.001252  -0.001212  -0.001001
         9  H  -0.000850   0.001755  -0.001251
        10  H   0.001226   0.001524  -0.002382
        11  H  -0.001039   0.001702   0.000025
        12  H   0.001792  -0.000807   0.000795
        13  C  -0.000020   0.000065   0.000039
        14  H  -0.001798  -0.001117   0.000914
        15  C  -0.000035  -0.000085  -0.000037
        16  H   0.000408  -0.005081  -0.002313
 ----------------------------------------------

Does anyone know what's wrong? Thanks!

Ignacio

Administrator

From: Uppsala

Registered: 2015-11-03

Posts: 1,085

Re: I got different velocities after reading in velocity.xyz

VELO=2 means the initial velocities are read in mass-weighted coordinates, but the printout is in unweighted coordinates. Multiply the output numbers by the square root of each atom's mass (in atomic units, not in dalton) and you should get the input numbers.