Electron Propagator Calculations in Gaussian

V. G. Zakrzewski and J. V. Ortiz

Bibliography

1. J. Linderberg and Y. Öhrn, Propagators in Quantum Chemistry, second edition, John Wiley and Sons, Hoboken, New Jersey (2004).

2. L. S. Cederbaum, and W. Domcke, Adv. Chem. Phys. 36, 205 (1977).

3. Y. Öhrn and G. Born, Adv. Quant. Chem. 13, 1 (1981).

4. L. S. Cederbaum, J. Phys. B 8, 280 (1975).

5. W. von Niessen, J. Schirmer and L. S. Cederbaum, Comput. Phys. Rep. 1, 57 (1984).

6. V. G. Zakrzewski, J. V. Ortiz, J. A. Nichols, D. Heryadi, D. L. Yeager and J. T. Golab, Int. J. Quant. Chem. 60, 29 (1996).

7. J. V. Ortiz, J. Chem. Phys. 104, 7599 (1996).

8. A. M. Ferreira, G. Seabra, O. Dolgounitcheva, V. G. Zakrzewski and J. V. Ortiz, Application and Testing of Diagonal, Partial Third-Order Electron Propagator Approximation, in Quantum-Mechanical Prediction of Thermochemical Data, 131, J. Cioslowski, ed., Kluwer, Dordrecht, 2001.

9. J. V. Ortiz, V. G. Zakrzewski, and O. Dolgounitcheva, One-Electron Pictures of Electronic Structure: Propagator Calculations of Photoelectron Spectra of Aromatic Molecules, in Conceptual Trends in Quantum Chemistry, Vol. 3, 465, E. S. Kryachko ed., Kluwer, Dordrecht, 1997.

10. V. G. Zakrzewski and J. V. Ortiz, Int. J. Quant. Chem., Quant. Chem. Symp. 28, 23 (1994).

11. V. G. Zakrzewski and J. V. Ortiz, Int. J. Quant. Chem. 53, 583 (1995).

12. J. V. Ortiz, The Electron Propagator Picture of Molecular Electronic Structure, in Computational Chemistry: Reviews of Current Trends, Vol. 2, 1-61, J. Leszczynski, ed., World Scientific, Singapore, 1997.

13. J. V. Ortiz, Adv. Quantum Chem. 35, 33 (1999).

Directions

• The keyword for both OVGF and P3 calculations is OVGF
• These calculations include SCF=tight HF calculation and integral transformation (l801,l804)
• Default mode for integral tranformation invoked by OVGF keyword is tran=iabc, i.e. integrals with 4 virtual indices are not built. The transformation can run with the keyword tran=abcd, which will save some CPU time during the OVGF calculation but take extra disk space and more time during the transformation step.
• G-94,98,03 use direct or semidirect integral transformation. One of the main parameters in the semidirect transformation is the number of orbitals per pass. It is regulated by option 16 for link 804.
• If link l804 is invoked directly in the additional command line (with extraoverlays in the main command line) then this is specified as 8/.....,16=n,.../1,4; where n is the number of orbitals per pass.
• If extraoverlays are not used, iop(8/16=n) in the command line will work.
• The OVGF and P3 options are described in detail in the source code's comments section, or in the Gaussian manual in the Options Section.
• Integral transformation imposes a Window of orbitals sometimes called the active space. This is set by Options 10=91, and Options 37=n1, 38=n2 defining the first and the last MO included in the transformation. (This is very helpful when a system under investigation is too large for one's computer resourses.) If Option 37 is 0 then an extra line (card) is read as an input specifying the first and last MOs used in transformation.
• OVGF/P3 calculations are controlled mostly by Option 11 in l908. The default choice is OVGF. Different decimal digits have different meanings.
• If you do not want to calculate all ionization energies by default (it takes time, you know), it is possible to specify the first and the last orbital for which the calculation is run by the option 11=100. It can be set by keyword iop(9/11=100); then the numbers of the first and the last MOs are given in the input after a blank line following previous input (such as Z-matrix, basis set, et cetera). One set of these numbers for alpha spin-orbitals and another set for beta spin-orbitals are needed. Do not forget that the number of inner MOs must be subtracted from the total number of MOs to get to these values.
• IOp(11) ... Flags for electron propagator calculations:
  • 0 ... Normal use of MO integrals.
  • 1 ... Force direct computation of contributions.
  • 2 ... Force direct computation of contributions.
  • 00 ... Normal production of intermediates (in-core if possible).
  • 10 ... Force use of sort for intermediates (l908 only if we need it at all?).
  • 100 ... Read window of MOs to refine in the same format as 801, but with two ranges on the same line for open-shell.
  • 1000 ... Force N**3 algorithm in GFSCMA.
  • 00000 ... Default (P3 for ionization energies)
  • 10000 ... P3 for ionization energies and electron affinities.
  • 20000 ... OVGF
  • 30000 ... OVGF + P3 for ionization energies (+ P3 for electron affinities if integrals are present)
  • 40000 ... 2nd order only
  • 100000 ... Read EMin, EMax, and pole strength warning level on one line. Link 909 only.

General Recommendations

Sample Inputs