oeprop(1)																 oeprop(1)

NAME

       oeprop - One-Electron Property Program

DESCRIPTION

       The  program  oeprop  computes  expectation  values of one-electron property operators using a one-particle density matrix computed from an
       eigenvector in PSIF_CHKPT or read in from an external file.  It is currently capable of performing Mulliken population analysis,  computing
       electric  multipole moments through octopole, electrostatic properties at atomic centers (electrostatic potential, electric field, electric
       field gradient, electron and spin density, dipolar anisotropic contribution to the hyperfine coupling constants), electron  and	spin  den-
       sity,  electron	and  spin density gradient, Laplacian of electron and spin densities, electrostatic potential over an arbitrary two-dimen-
       sional (planar) rectangular grid, and molecular orbitals values over an arbitrary three-dimensional rectangular grid.  Miscellaneous  capa-
       bilities  include computation of the relativistic first-order one-electron corrections to the energy (mass-velocity and Darwin terms), con-
       struction of natural molecular orbitals from one-particle density read from an external file (NOs can be written to PSIF_CHKPT) and  compu-
       tation  of  spatial  extents - expectation values of X^2, Y^2, Z^2, and R^2 operators - of total electron density and of individual MOs (if
       READ_OPDM = false) or natural (if READ_OPDM = true) orbitals (MPMAX must be set to a value greater than 1 for  computing  these	entities).
       Spatial extents should be used cautiously, since they depend on the reference point.

REFERENCES

       Mulliken population analysis

       1.     Electronic  Population Analysis on LCAO-MO Molecular Wave Functions.  R. S. Mulliken, J. Chem. Phys. 23, 1833 (1955), ibid. 23, 1841
	      (1955), ibid.  36, 3428 (1962).

       Recurrence relations for one-electron integrals over Cartesian Gaussian functions.

       1.     Efficient recursive computation of molecular integrals over Cartesian Gaussian functions. S. Obara and A. Saika, J. Phys. Chem.  84,
	      3963 (1986).

       Fundamental physical constants and conversion factors.

       1.     CRC Handbook of chemistry and physics. Edited by D. R. Lide. 73rd edition (1992-1993).

FILES REQUIRED

	   input.dat	    - Input file
	   PSIF_CHKPT	    - Checkpoint file

FILES UPDATED

	   output.dat
	   dipmom.dat	    -	Dipole moments
	   esp.dat	    -	Electrostatic potential on a 2D grid
	   edens.dat	    -	Electron density on a 2D grid
	   edgrad.dat	    -	Electron density gradient on a 2D grid
	   edlapl.dat	    -	Laplacian of the electron density on a 2D grid
	   sdens.dat	    -	Spin density on a 2D grid
	   sdgrad.dat	    -	Spin density gradient on a 2D grid
	   sdlapl.dat	    -	Laplacian of the spin density on a 2D grid
	   mo.dat	    -	Molecular orbital/Density values on a 3D grid
	   mo.pov	    -	MegaPov input file for rendering an image of mo.dat
	   mo.cube	    -	Molecular orbital(s) on a 3D grid in Gaussian94 Cube format
	   dens.cube	    -	Electron/spin density(s) on a 3D grid in Gaussian94 Cube format

INPUT FORMAT

       Most of the keywords are not neccessary for routine tasks. The following keywords are valid:

       WFN = boolean
	      Type of the wavefunction. This keyword is a "macro" that allows user to set most of the necessary keywords. The following values are
	      recognized :

	      WFN = SCF - equivalent to READ_OPDM = false;

	      WFN = DETCI  - equivalent to READ_OPDM = true, OPDM_FILE = 40, OPDM_BASIS = AO, OPDM_FORMAT = TRIANG;

	      WFN = CCSD - equivalent to EAD_OPDM = true, OPDM_FILE = 79, OPDM_BASIS = AO, OPDM_FORMAT = TRIANG;

	      WFN = QVCCD - equivalent to READ_OPDM = true, OPDM_FILE = 76, OPDM_BASIS = SO, OPDM_FORMAT = TRIANG;

       READ_OPDM = boolean
	      This flag specifies if the one-particle density matrix to be read from disk.  Default is false.

       OPDM_FILE = integer
	      Specifies one-particle density matrix file number. Default is 40 (master file).  To provide backward compatibility with the  earlier
	      PSI  property packages (proper, ciprop, ccprop) special format of the density file is assumed when OPDM_FILE = 40 (computing proper-
	      ties from CI density - ciprop compatibility mode) and OPDM_FILE = 79 (computing properties from CC density  -  ccprop  compatibility
	      mode).   As of now, in generic case onepdm must be written in the very beginning of the file. In the future PSI will have a standard
	      onepdm file.

       OPDM_BASIS = string
	      This option may not exist in the future. As of February 1st, 1998, a standard for the onepdm file format has not been set. This key-
	      word should be set to either "SO" (read in onepdm matrix in SO basis) or "AO" (in AO basis). Default is "SO".

       OPDM_FORMAT =  string
	      This  option  may  not exist in the future. This keyword should be set to either "TRIANG" (read in onepdm matrix in lower triangular
	      form) of "SQUARE" (in square form). Default is "TRIANG"

       ASYMM_OPDM =  boolean
	      This flag specifies whether one-particle density matrix has to be symmetrized.  Must be set to true if generic non-symmetric  onepdm
	      to  be  read  (for example, from a coupled-cluster program). This keyword is for code development only. Existing PSI CC codes now in
	      use produce symmetric onepdm, therefore there is no need to use this keyword.  Default is false.

       ROOT = integer
	      This specifies which root to do the excited state analysis for.  The appropriate one particle density matrix will be read from disk.
	      Currently implemented for DETCI and DETCAS wavefunctions.

       MPMAX = integer
	      This integer between 1 and 3 specifies the highest electric multipole moment to be computed.

	      MPMAX = 1 - only electric dipole moment will be computed (default);

	      MPMAX  =	2 - electric dipole and quadrupole moments will be computed; MPMAX = 3 - electric dipole, quadrupole, and octopole moments
	      will be computed.

       MP_REF integer
	      This parameter specifies the reference point for the electric multipole moments calculation.

	      MP_REF = 0 (default) or 1 - the center of mass;

	      MP_REF = 2 - the origin of the space coordinate system;

	      MP_REF = 3 - the center of electronic charge;

	      MP_REF = 4 - the center of nuclear charge;

	      MP_REF = 5 - the center of net charge.

	      CAUTION : According to classical electrodynamics, the electric 2^(n+1)-pole moment is independent of the reference point only if the
	      electric	2^(n)-pole  moment is vanishing. It means that the dipole moment will depend on the reference point if the total charge of
	      the system is non-zero. By analogy, electric quadrupole moment will depend on the reference point if the system  possesses  non-zero
	      electric dipole moment, etc.

       MP_REF_XYZ = real_vector
	      This  vector specifies the coordinates of the reference point. If this keyword is present in the input MP_REF keyword will be disre-
	      garded.

       NUC_ESP = boolean
	      This flag specifies if electrostatic properties will be computed at the nuclei. Current list includes electrostatic potential, elec-
	      tric  field,  electric  field gradient, electron and spin density, and anisotropic constribution to the hyperfine coupling constants
	      (the latter two require setting SPIN_PROP to true). Default is true.

       GRID = integer
	      Specifies type of property to be evaluated over a grid.

	      GRID = 0 (default) - compute nothing;

	      GRID = 1 - electrostatic potential on a two-dimensional grid;

	      GRID = 2 - electron density (spin density if SPIN_PROP is set to true) on a two-dimensional grid;

	      GRID = 3 - electron density gradient (spin density gradient if SPIN_PROP is set to true) on a two-dimensional grid;

	      GRID = 4 - Laplacian of the electron density (Laplacian of the spin density if SPIN_PROP is set to true) on a two-dimensional  grid.
	      According to the convention used in the field, what actually gets plotted are the Laplacians taken with negative sign.

	      GRID = 5 - values of molecular orbitals on a three-dimensional grid.

	      GRID = 6 - values of the electron density (spin density gradient if SPIN_PROP is set to true) on a three-dimensional grid.

       GRID_FORMAT = string
	      Specifies  in which format the grid output will be produced.  Currently, PLOTMTV (default for 2-d grids), MEGAPOVPLUS (available for
	      3-d grids), and GAUSSCUBE(default for 3-d grids) are supported.

       MO_TO_PLOT = vector
	      Specifies indices of the molecular orbitals to be computed on the 3-d grid. Indices can be specified as:

	      unsigned integer - index in Pitzer ordering (ordered accoring to irreps, not eigenvalues).  Ranges from 1 to the number of MOs.

	      signed integer - index with respect to Fermi level. +1 means LUMO, +2 means second lowest virtual orbital, -1 means HOMO, etc.

	      All indices have to be either unsigned or signed, you can't mix and match, or you will get unpredictable	results.   Default  is	to
	      compute HOMO and LUMO.

       GRID_ORIGIN = real_vector
	      Specifies  the  origin  of  the  grid.  A  rectangular grid box which envelops the entire molecule will be computed automatically if
	      GRID_ORIGIN is missing, however, there is no default for 2-d grids.

       GRID_UNIT_X = real_vector
	      This vector specifies the direction of the first (x) side of the grid.  It doesn't have have to be of  unit  length.   There  is	no
	      default for 2-d grids.

       GRID_UNIT_Y = real_vector
	      The  same  for the second (y) side. It doesn't have to be of unit length or even orthogonal to GRID_UNIT_X.  There is no default for
	      2-d grids.

       GRID_XY0 = real_2d_vector
	      Specifies the coordinates of the lower left corner of the grid rectangle	in  the  2D  coordinate  system  defined  by  GRID_ORIGIN,
	      GRID_UNIT_X, and GRID_UNIT_Y.  There is no default.

       GRID_XY1 = real_2d_vector
	      Specifies  the  coordinates  of  the  upper  right  corner of the grid rectangle in the 2D coordinate system defined by GRID_ORIGIN,
	      GRID_UNIT_X, and GRID_UNIT_Y.  There is no default.

       GRID_XYZ0 = real_3d_vector
	      Specifies the coordinates of the far lower left corner of the  grid  box	in  the  3D  coordinate  system  defined  by  GRID_ORIGIN,
	      GRID_UNIT_X, GRID_UNIT_Y, and the cross-product of the latter two. There is no default.

       GRID_XYZ1 = real_3d_vector
	      Specifies  the  coordinates  of  the  near  upper  right	corner of the grid box in the 3D coordinate system defined by GRID_ORIGIN,
	      GRID_UNIT_X, GRID_UNIT_Y, and the cross-product of the latter two. There is no default.

       NIX = integer
	      The number of grid point along x direction. This parameter has to be greater than 1. Default is 20.

       NIY = integer
	      The same as NIX for y direction. Default is 20.

       NIZ = integer
	      The same as NIX for z direction. Default is 20.

       GRID_ZMIN = double
	      Lower limit on displayed z-values for contour plots of electron density and its Laplacian. Default is 0.0

       GRID_ZMAX = double
	      Upper limit on displayed z-values for contour plots of electron density and its Laplacian. Default is 3.0

       EDGRAD_LOGSCALE = integer
	      Controls logarithmic scaling of the produced electron density gradient plot. Turns the scaling off if set  to  zero,  otherwise  the
	      higher value - the stronger the gradient field will be scaled.  Recommended value (default) is 5.

       SPIN_PROP = boolean
	      Flag for computing spin properties (Mulliken population analysis of alpha and beta densities, spin densities and anisotropic contri-
	      butions to the hyperfine coupling constants at atomic centers). Default is false.

       PRINT = integer
	      This is the most important keyword - it determines amount of information printed. The following values are currently used :

	      PRINT = 0 - quiet mode - print out essential results only - "compact" results of Mulliken population  analysis,  electric  multipole
	      moments, and electrostatic properties;

	      PRINT = 1 (default) - all of the above plus list of tasks to be performed and list of caculation parameters;

	      PRINT = 2 - all of the above plus Mulliken AO population matrix and electronic and nuclear components of electric dipole moment;

	      PRINT = 3 - all of the above plus density matrix in AO basis and dipole moment integrals in AO (and SO) basis;

	      PRINT = 4 - all of the above plus basis set information, natural orbitals in terms of symmetry orbitals, overlap matrix;

	      PRINT >= 5 - all of the above plus coupling coefficient vectors, an occupation vector, and a modified Z-vector in MO basis.

       PRINT_NOS = boolean
	      If  WRTNOS = TRUE and this option is also TRUE, the natural orbitals will be printed to output before they are written to the check-
	      point file.

       WRTNOS = boolean
	      If TRUE, the natural orbitals will be written to the checkpoint file.

GRID OUTPUT AND PLOTTING

       Currently, oeprop produces output of two-dimensional grids ready for plotting with a program PLOTMTV version 1.3.2. The program is  written
       by  Kenny  Toh  (ktoh@td2cad.intel.com),  software  developer for the Technology CAD Department, Intel Corp, Santa Clara.  It is a freeware
       package, and can be downloaded off the Internet.

       Three-dimensional grids are output in format suitable for plotting with a program MegaPov version 0.5. This freeware program is	a  patched
       version of POV-Ray. It is developed by a number of people, and can be downloaded off the Internet (go to http://nathan.kopp.com/patched.htm
       to find out more info). To render an MO or density image, edit (if necessary) command file mo.pov created by oeprop , and execute  megapov-
       plus +Imo.pov For more options run megapovplus -h

								   March 30, 2001							 oeprop(1)