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Contents 1 General control statements 1.1 .PRINT 1.2 .ABUNDANCIES 1.3 .RKBIMP 2 Predefined electric properties 2.1 .DIPOLE 2.2 .QUADRUPOLE 2.3 .EFG 2.4 .NQCC 2.5 .POLARIZABILITY 2.6 .FIRST ORDER HYPERPOLARIZABILITY 2.7 .VERDET 2.8 .TWO-PHOTON 3 Predefined magnetic properties 3.1 .NMR 3.2 .SHIELDING 3.3 .MAGNET 3.4 .SPIN-SPIN COUPLING 3.5 .DSO 3.6 .NSTDIAMAGNETIC 4 Other predefined properties 4.1 .MOLGRD 4.2 .PVC 4.3 .RHONUC 4.4 .EFFDEN 5 References

This section allows for the evaluation of a large number of molecular properties. Available properties include:

• Expectation values (e.g. dipole moment and electric field gradients).
• Linear response properties (e.g. polarizability and NMR parameters).
• Quadratic response properties (e.g. hyperpolarizabilities).

For convenience some common properties can be specified directly in this section, which means that the user in principle does not need to know how they are calculated. Note, however, that response functions are by default static, but frequencies can be added in the relevant subsections.

Properties which are not predefined must be specified in detail in the relevant input section (see the specification of one-electron operators).

By default no properties are calculated.

General control statements

.PRINT

Print level.

Default:

.PRINT
 0

.ABUNDANCIES

For properties that make reference to isotopes, give threshold level (in % abundance) for isotopes to print.

Default:

.ABUNDANCIES
 1.0

.RKBIMP

Import coefficients calculated with restricted kinetic balance (RKB) in a calculation using unrestricted kinetic balance (UKB). This option is a simple way to generated restricted magnetic balance for the calculation of NMR shieldings. This option works in the general SO case, but not in the spinfree case since spinfree calculations are not possible with UKB.

Predefined electric properties

.DIPOLE

Evaluate the electronic dipole moment (expectation value).

.QUADRUPOLE

Evaluate the electronic quadrupole moment (expectation value).

.EFG

Evaluate electric field gradients (expectation values).

Atomic centers may be restricted with .SELECT under **INTEGRALS.

.NQCC

Evaluate nuclear quadrupole coupling constants (expectation values).

Atomic centers may be restricted with .SELECT under **INTEGRALS.

.POLARIZABILITY

Evaluate the static electronic dipole polarizability tensor (linear response).

.FIRST ORDER HYPERPOLARIZABILITY

Evaluate static electronic dipole first-order hyperpolarizability tensor (quadratic response). Results are also given for the static electronic dipole polarizability.

.VERDET

Evaluate Verdet constants^[1] (quadratic response) for a dynamic electric field corresponding to Ruby laser wavelength of 694 nm and a static magnetic field along the propagation direction of the light beam (in this case, the default frequencies of the quadratic response function thus become ω_B = 0.0656 and ω_C = 0.0). A Verdet calculation cannot be specified in combination with other quadratic response calculations.

The frequencies can be changed using .BFREQ in *QUADRATIC RESPONSE.

.TWO-PHOTON

Evaluate two-photon absorption cross sections (quadratic response). Give the number of desired states in each boson symmetry. Cannot be specified in combination with other quadratic response calculations.

Example: Point group with four boson irreps, (e.g. C_2v).

.TWO-PHOTON
 5 5 5 0

Predefined magnetic properties

.NMR

Evaluate nuclear magnetic shieldings and indirect spin-spin couplings (linear response).

Atomic centers may be restricted with .SELECT under **INTEGRALS.

.SHIELDING

Evaluate nuclear magnetic shieldings (linear response). Print level 2 gives tensor and longer output. Print level 4 gives the raw values in symmetry coordinates as well.

Atomic centers may be restricted with .SELECT under **INTEGRALS.

.MAGNET

Evaluate the magnetic susceptibilities tensor (linear response and expectation values).

.SPIN-SPIN COUPLING

Evaluate indirect spin-spin couplings (linear response).

Atomic centers may be restricted with .SELECT under **INTEGRALS.

.DSO

Evaluate the diamagnetic contribution to indirect spin-spin couplings as an expectation value.

Atomic centers may be restricted with .SELECT under **INTEGRALS.

.NSTDIAMAGNETIC

Evaluate the diamagnetic contribution to nuclear magnetic shieldings as an expectation value.

Atomic centers may be restricted with .SELECT under **INTEGRALS.

Other predefined properties

.MOLGRD

Evaluate the molecular gradient, i.e. where X_A are the coordinates of the nuclei. This is an expectation value of one- and two-electron operators. Normally the molecular gradient evaluation is not invoked explicitly with this keyword but rather implicitly in the geometry optimization module.

.PVC

Calculate matrix elements over the nuclear spin-independent parity-violating operator, e.g. calculate energy differences between enantiomers ^[2].

.RHONUC

Calculate electronic density at the nucleus(nuclei).

Atomic centers may be restricted with .SELECT under **INTEGRALS.

.EFFDEN

Calculate effective electronic density at the nucleus(nuclei).^[3].

Atomic centers may be restricted with .SELECT under **INTEGRALS.

References

1. ↑ Ulf Ekstrom and Patrick Norman and Antonio Rizzo, Four-component Hartree--Fock calculations of magnetic-field induced circular birefringence---Faraday effect---in noble gases and dihalogens, The Journal of Chemical Physics 122, 074321 (2005) electronic version.
2. ↑ J. K. Lærdahl and P. Schwerdtfeger, Fully relativistic ab initio calculations of the energies of chiral molecules including partiy-violating weak interactions, Phys. Rev. A 60, 4439 (1999) electronic version.
3. ↑ S. Knecht, S. Fux, R. van Meer, L. Visscher, M. Reiher, T. Saue, Mössbauer spectroscopy for heavy elements: a relativistic benchmark study of mercury, Theor. Chem. Acc. 129, 631-650 (2011) electronic version.