debian man page for mp2r12

Psi Release 2.0 						1

mp2r12(1)	   PSI COMMANDS FOR UNIX USERS		mp2r12(1)

NAME
     mp2r12  - calculates the MP2-R12 energy in standard approxi-
     mation A for closed-shell systems.

DESCRIPTION
     The program mp2r12 determines  the  linear-R12  second-order
     Moller-Plesset energy for closed-shell systems.  Input inte-
     grals must come from the restricted transformation available
     in the TRANSQT program.  Frozen orbitals are not allowed, as
     the basis sets used in linear-R12 computations employ  basis
     sets with more than enough flexibility to describe core-cor-
     relation effects correctly.

REFERENCES
     Moller-Plesset original paper:

     1.   C. Moller and M. S. Plesset, "Note on an  Approximation
	  Treatment  for  Many-Electron Systems", Phys. Rev., 46,
	  618(1934).

     Linear R12 theory formulation:

     2.   W. Kutzelnigg and  W.  Klopper,  "Wave  functions  with
	  terms linear in the interelectronic coordinates to take
	  care of the correlation cusp.  I. General  Theory",  J.
	  Chem. Phys., 94, 1985(1991).

     MP2-R12/A programmable expressions:

     3.   W. Klopper, "Limiting values for Moller-Plesset second-
	  order correlation energies  of  polyatomic  systems:	A
	  benchmark  study  on	Ne, HF, H2O, N2, and He...He", J.
	  Chem. Phys., 102, 6168(1995).

FILES REQUIRED
	  input.dat
	  FILE30
	  FILE72	(electron repulsion integrals, produced by transqt)
	  FILE79	(integrals of r12 operator, produced by transqt)
	  FILE80	(integrals of [r12,T2] operator, produced by transqt)

FILES GENERATED
	  output.dat

Psi Release 2.0    Last change: 06 August, 1999 		1

mp2r12(1)	   PSI COMMANDS FOR UNIX USERS		mp2r12(1)

INPUT OPTIONS
     mp2r12 has the following options:

     PRINT_LVL = integer
	  Determines the verbosity of the  printing  information.
	  A  print  value of 0 gives minimal information, while 5
	  gives debugging information (do NOT  use  print  levels
	  above 3 for more than 20 basis functions).  The default
	  is 0.

     TOLERANCE = integer
	  This gives the exponent of the  cutoff  value  for  the
	  elimination  of two-electron integrals from the list of
	  those on disk.  The default is 14, giving a  cutoff  of
	  1e-14.

     FROZEN_DOCC = int_array
	  Number  of frozen doubly-occupied orbitals in each sym-
	  metry block.	Default is a vector of zeroes.

     FROZEN_UOCC = int_array
	  Number of frozen unoccupied orbitals in  each  symmetry
	  block.  Default is a vector of zeroes.

     C_LIMIT = boolean
	  Instead  of  using  variationally  optimized	C-coeffi-
	  cients, use limiting values (1/2 for singlet pairs, 1/4
	  for triplet pairs).  Default is false.

Psi Release 2.0    Last change: 06 August, 1999 		2