ORCA Max Plank Institute
ORCA
is a multi-purpose quantum-chemical software package. It features a wide variety of
methods ranging from semi-empirical methods to density functional theory to correlated single-
and multi-reference wave-function based methods. Environmental as well as relativistic effects
can be taken into account.
ORCA
is the leading software tool in the calculation of
spectroscopic properties of open-shell molecules.
RKS or UKS
This are the flags to indicate a DFT calculation.
it stands for, Restricted Kohn Sham for closed shell systems or
Unrestricted Kohn Sham for open shell systems.
PBE Density functional to calculate the
exchange correlation energy. Altenatively could be PBE0, B3LYP etc...
Opt Default Single Point. Indicates a
geometry optimization calculation.
NumFreq Numerical Derivatives. Alternative AnFreq
that calculates the faster analytical frequencies but no the dipole changes.
#ORCA Basic Input DFT calculation
! UKS PBE TZVP
! PMODEL #Initial density guess
! XYZfile #Type of coordinates
! TightSCF #SCF convergence criteria
! PAL8 #Number of core processors
! Opt #Geometry optimization
! NumFreq #Numerical Frequency
! NumFreq #Vibrational analysis.
%method
Grid 2 #110 grid points for the SCF
FinalGrid 4 #302 grid points
end
#Type Charge Multiplicity
* xyz 0 1
Symbol X1 Y1 Z1
C X2 Y2 Z2
H X3 Y3 Z3
Pt X4 Y4 Z4
*