Updates after submittals to EPAPS:

27 Feb 2001
===========
The Fortran 90 program "cart2euler.f" added to our ftp-site:
ftp://ftp.theochem.kun.nl/pub/theochem/gerritg/E-PRLTAO-84-060018/cart2euler.f
This program converts cartesian coordinates of two water molecules to the
Euler angles required by "sapt5s.f". The Euler angles are shown
in the PostScript file "geometry.ps".

========================== README.TXT ===============================

ARTICLE INFORMATION:         E-PRLTAO-84-060018       [LL7541]

Journal:     Physical Review Letters, 1 May 2000,  VOL. 84, Issue 18, pages 4072
  
All Authors:   Gerrit C. Groenenboom, Eric M. Mas, Robert Bukowski,
   Krzysztof Szalewicz, Paul E. S. Wormer, and Ad van der Avoird.

Title:Water pair and three-body potential of spectroscopic quality from ab initio calculations.

DEPOSIT INFORMATION

Description:
   Fortran 77 routines to evaluate the SAPT-5s and (tuned) SAPT-5st potentials.
   Routines are included for both the H2O pair potential and the D2O pair
   potential. An example program with input and corresponding output is 
   provided.

Total No. of Files: 4

Filenames: README.TXT +                    
           sapt5s.f            (fortran 77 routines and test program)
           example.dat         (example input)
           example.out         (corresponding output)

Filetypes: all ASCII.

Special Instructions: See Below

Contact Information:
        Dr. Gerrit C. Groenenboom
        Inst. of Theo. Chem.
        Univ. of Nijmegen
        Toernooiveld 1
        6525 ED Nijmegen, NETHERLANDS

Phone: 011-31-243653034      Fax:     011-31-243653041              Email:   gerritg@theochem.kun.nl

Special instructions:

(1) Instructions for usage of the fortran 77 routines.
(2) Definition of the coordinates and positions of the sites.
(3) Information on the equilibrium geometry for test purposes.

(1) Instructions for usage of the fortran 77 routines.
======================================================
The file sapt5s.f contains:

      program test_potential
      subroutine sapt5s_init
      subroutine sapt5st_init
      subroutine ss_dshift
      subroutine ss_eval(coords,etotal)
           entry ss_init(nip,ip,np,p)
           entry ss_shift(shift)
           entry ss_print(iout,iprint)
      subroutine g_euler(alpha,beta,gamma,R)
      real*8 function f_damp(br,n)

The parameters are defined in comments in the routines. The call sequence is
defined here:

Before the potential can be evaluated it must be initialized with:
      CALL SAPT5S_INIT
for the SAPT5-s potential, or
      CALL SAPT5ST_INIT
for the SAPT5-st (tuned) potenial. The potential for the H2O dimer may now
be evaluated with:
      CALL SS_EVAL(COORDS,E)
To evaluate the D2O dimer potential use
      CALL SS_DSHIFT
once after the initialization call.
To obtain detailed information on the potentials use the entry point:
      CALL SS_PRINT(IOUT,IPRINT)
after the initialization (or after the call to SS_DSHIFT).

The entry point SS_INIT(nip,ip,np,p) is used by the SAPT5S_INIT and
SAPT5ST_INIT subroutines to set both the real and integer parameters that
define the potential.  The subroutine G_EULER(alpha,beta,gamma,R) converts from
Euler parameters to a 3x3 rotation matrix. The function F_DAMP(br,n) evaluates
the Tang-Toennies damping function.

(2) Definition of the coordinates and positions of the sites.
=============================================================
The cartesian coordinates of the monomer sites can be found in DATA statements
in the subroutines SAPT5S_INIT or SAPT5ST_INIT. See also entry point SS_PRINT.

The internal coordinates are defined in the subroutine SS_EVAL. The first 30
executable statements of this subroutine show how to compute the cartesian
coordinates of the sites in the dimer for given sets of Euler angles and the
center of mass distance.

The zyz Euler angles are defined in the subroutine G_EULER.

(3) Information on the equilibrium geometry for test purposes.
==============================================================
SAPT5-s:
Euler angles:   0.00 119.19 0.00 180.00 129.27 90.00 (degrees)
R=5.5980538 (bohr)
V=-0.007746338 hartree (-1700.12 cm-1)

SAPT5-st:
Euler angles:   0.00 118.49 0.00 180.00 123.69 90.00 (degrees)
R=5.53165707028521 (bohr)
V=-0.008014545 hartree (-1758.99 cm-1)

Nijmegen, February 6, 2000.
=====================================================================