The Formatted HISTORY File

The formatted HISTORY file is written by the subroutine TRAJECT and has the following structure.

record 1 (a80)

header 		 a80 		 file header 

record 2 (3i10)

keytrj 		 integer 		 trajectory key (see table 4.3)

imcon 		 integer 		 periodic boundary key (see table 4.6)

natms 		 integer 		 number of atoms in simulation cell

For timesteps greater than nstraj the HISTORY file is appended at intervals specified by the traj directive in the CONTROL file, with the following information for each configuration:

record i (a8,4i10,f12.6)

timestep 		 a8 		 the character string ``timestep''

nstep 		  integer 		 the current time-step

natms 		 integer 		 number of atoms in configuration

keytrj 		 integer 		 trajectory key (again) 

imcon 		 integer 		 periodic boundary key (again) 

tstep 		 real 		 integration timestep 

record ii (3g12.4) for imcon $>$ 0

cell(1) 		 real 		 x component of $a$ cell vector

cell(2) 		 real 		 y component of $a$ cell vector

cell(3) 		 real 		 z component of $a$ cell vector

record iii (3g12.4) for imcon $>$ 0

cell(4) 		 real 		 x component of $b$ cell vector

cell(5) 		 real 		 y component of $b$ cell vector

cell(6) 		 real 		 z component of $b$ cell vector

record iv  (3g12.4) for imcon $>$ 0

cell(7) 		 real 		 x component of $c$ cell vector

cell(8) 		 real 		 y component of $c$ cell vector

cell(9) 		 real 		 z component of $c$ cell vector

This is followed by the configuration for the current timestep. i.e. for each atom in the system the following data are included:

record a (a8,i10,2f12.6) 

atmnam 		 a8 		 atomic label

iatm 		 i10 		  atom index

weight 		 f12.6 		 atomic mass (a.m.u.)

charge 		 f12.6 		 atomic charge (e) 

record b (3e12.4)

xxx 		 real 		 x coordinate

yyy 		 real 		 y coordinate

zzz 		 real 		 z coordinate

record c (3e12.4) only for keytrj $>$ 0

vxx 		 real 		 x component of velocity

vyy 		 real 		 y component of velocity

vzz 		 real 		 z component of velocity

record d (3e12.4) only for keytrj $>$ 1

fxx 		 real 		 x component of force

fyy 		 real 		 y component of force

fzz 		 real 		 z component of force

Thus the data for each atom is a minimum of two records and a maximum of 4.