MOLPRO

19 THE MCSCF PROGRAM MULTI 141
19.7 Calculating expectation values
By default, the program calculates the dipole expectation and transition moments. Further
expectation values or transition properties can be computed using the TRAN, TRAN2 and
EXPEC, EXPEC2 directives.
19.7.1 Matrix elements over one-electron operators
EXPEC,oper 1 ,oper 2 ,...,oper n
TRAN,oper 1 ,oper 2 ,...,oper n
Calculate expectation values and transition matrix elements for the given one-electron operators.
With EXPEC only expectation values are calculated. oper i is a codeword for the operator. The
available operators and their associated keywords are given in section 6.13.
19.7.2 Matrix elements over two-electron operators
EXPEC2,oper 1 ,oper 2 ,...,oper n
TRAN2,oper 1 ,oper 2 ,...,oper n
Calculate transition matrix elements for two-electron operators. This is presently only useful for
angular momentum operators. With EXPEC2 only diagonal matrix elements will be computed.
For instance
TRAN2,LXX
TRAN2,LYY
calculates matrix elements for L 2 x
calculates matrix elements for L 2 y
TRAN2,LXZ calculates matrix elements for 1 2 (L xL z + L z L x )
TRAN2,LXX,LYY,LZZ
calculates matrix elements for L 2 x, L 2 y, and L 2 z . The matrix elements
for the sum L 2 are also printed.
19.7.3 Saving the density matrix
DM,[spindens]
If the DM directive is given, the first order density matrix in AO basis is written to the dump
record specified on the ORBITAL card (default 2140.2). If no ORBITAL card is present, but
a record is specified on a NATORB, CANORB, or LOCORB card, the densities are saved to the
first record occurring in the input. In a state-averaged calculation the SA-density, as well the
individual state densities, are saved. See section 4.11 for information about how to recover any
of these densities for use in later programs.
Of spindens is a number greater than zero, the spin density matrices are also saved. Note that a
maximum of 50 density matrices can be saved in one dump record.
If no DM directive is given), the first order density matrix is saved in single-state calculations,
and only the stage-averaged density matrix in state-averaged calculations.
19.8 Miscellaneous options
All commands described in this section are optional. Appropriate default values are normally
used. Note that printing of the orbitals and civectors can also be requested using the global
GPRINT command, or by giving NATORB or CANORB options.