# Example: ESR g-tensor, A-tensor, self consistent spin-orbit coupling: VO¶

Download VO_collinear.run

#! /bin/sh

# The ESR parameters of VO are calculated with the collinear approximation for
# unrestricted Spin-Orbit coupled calculations. In this example the VO-molecule
# has three unpaired electrons.

# You calculate Electron Spin Resonance properties with the keywords ESR and
# QTENS. ESR is a block-type key and is used to compute the G-tensor or the
# Nuclear Magnetic Dipole Hyperfine interaction. QTENS is a simple key and
# invokes the computation of the Nuclear Electric Quadrupole Hyperfine
# interaction.

# Proper usage of the key ESR requires that you do one of the following:

# A Spin-Orbit calculation, spin-restricted, with exactly one unpaired electron,
# or (b) A Spin-Orbit calculation, spin-unrestricted in the collinear
# approximation, or (c) No Spin-Orbit terms and spin-unrestricted. In case (a)
# and (b) you obtain the G-tensor. In case (b) and (c) you get the Magnetic
# Dipole Hyperfine interaction.

# Note: in case (a) the program also prints a Magnetic Dipole Hyperfine
# interaction data, but these have then been computed without the terms from the
# spin-density at the nucleus. Note: in case (b) and (c) one can have more than
# one unpaired electron. Note: in case (b) one has to use symmetry NOSYM.

# Two calculations are performed:

# Scalar relativistic spin-unrestricted (case c)
# Spin-Orbit relativistic spin-unrestricted collinear (case b)

# After the preliminary calculations (DIRAC, to get the relativistic TAPE12 file
# with relativistic potentials, and the Create runs), we first calculate the
# Dipole Hyperfine interaction: a spin- unrestricted calculation without Spin-
# Orbit coupling.

# Note that one has to use ALLPOINTS in the calculation for a linear molecule to
# get results for the nuclear magnetic dipole hyperfine interaction. For an
# accurate calculation of the hyperfine interaction the numerical quality is set
# to VeryGood.

$ADFBIN/adf <<eor Atoms V 0 0 0 O 0 0 1.589 End XC GGA Becke Perdew End ESR End Qtens Allpoints Unrestricted ZFS Charge 0 3 Relativistic Scalar ZORA Basis Type TZ2P Core None End NumericalQuality verygood eor rm TAPE21 logfile # Then a spin-orbit coupled spin-unrestricted calculation is performed using the # collinear approximation. Note that symmetry NOSYM is used.$ADFBIN/adf  <<eor
Atoms
V 0 0 0
O 0 0 1.589
End
XC
GGA Becke Perdew
End
SCF
LISTf
END
ESR
End
Qtens
Symmetry nosym
Unrestricted
Collinear
Relativistic Spinorbit ZORA
Basis
Type TZ2P
Core None
End
NumericalQuality verygood
eor

rm TAPE21 logfile