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Contents 1 **INTEGRALS -- Integral directives 1.1 .NUCMOD 1.2 .SELECT 1.3 .PHASEO 1.4 .GAUGEO 1.5 .DIPORG 1.6 .MAGCOR 1.7 .PRINT 1.8 References

**INTEGRALS -- Integral directives

.NUCMOD

Nuclear model.

Point nucleus:

.NUCMOD
 1

Gaussian charge distribution (default):

.NUCMOD
 2

The point nucleus model is useful to compare Lévy-Leblond type calculations with regular nonrelativistic calculations done with another code, e.g. DALTON. The two methods should give precisely the same energies.

For the Gaussian charge distribution the default exponents are in accordance with values proposed by Visscher and Dyall ^[1], see also the web-site [1]. If desired, other exponents may be specified in the basis file.

Advanced options

.SELECT

Restrict range of nuclei in one-electron integrals involving single atomic centers, for example electric field gradients.

Example: Restrict range to four nuclei, the nuclei 1, 3, 7, and 8.

.SELECT
 4
 1
 3
 7
 8

.PHASEO

Origin appearing in the London atomic orbital phase-factors.

Default:

.PHASEO
 0.0 0.0 0.0

This is the text from the DALTON manual. We wonder if it is used for other integrals, in the code in her1int.F it is the final "else" option.

.GAUGEO

Gauge origin.

Default:

.GAUGEO
 0.0 0.0 0.0

.DIPORG

Origin for all moment integrals, including the dipole (dipole is independent of origin only for neutral systems).

Default:

.DIPORG
 0.0 0.0 0.0

.MAGCOR

Print the symmetrized nuclear magnetic moments; this corresponds to taking symmetry combinations of rotations, not coordinates, at each nuclear center. The numbering is used in labels of various magnetic integrals.

Programmers options

.PRINT

General print level in HERMIT.

Default:

.PRINT
 1

References

1. ↑ L. Visscher and K. G. Dyall, Dirac-Fock atomic electronic structure calculations using different nuclear charge distributions, At. Data Nucl. Data Tabl. 67, 207 (1997) electronic version.