[molpro-user] Help please ! ABOUT_CUBIC_FORCE_CONSTANTS

Hari D Pandey hpandey at unr.edu
Wed Feb 11 07:14:59 GMT 2015



Dear all MOLPRO users,

I am a new MOlpro user. I want to calculate anharmonic force constants. I have used following input file. 
Please help me how do I  print cubic force/quartic constants 
 I used the keyword prtfc=1 but  I never  get force coefficients  in my .log or .out file. 
Please help me what could be correct input file for such purpose.
Your help is highly appreciated.
Thanks in advance.


***water
memory,20,m
basis=vdz
orient,mass
geomtyp=xyz
geometry={
   3
Water
O          0.0675762564        0.0000000000       -1.3259214590
H         -0.4362118830       -0.7612267436       -1.7014971211
H         -0.4362118830        0.7612267436       -1.7014971211
}

hf
mp2
optg                                     !(1) optimizes the geometry
{frequencies,symm=auto                   !(2) compute harmonic frequencies
print,low=50}

label1
{hf
start,atden}
{mp2
cphf,1}

{surf,start1D=label1,sym=auto            !(3) generate potential energy surface
 intensity,dipole=2}
poly,dipole=1                            !(4) converts potential energy surface
                                         !    to a polynomial representation
vscf,type=poly                           !(5) do a VSCF calculation
vci,type=poly,pmp=3,version=1            !(6) do a VCI calculation
vci,type=poly,pmp=3,version=2
vci,type=poly,pmp=3,version=3
put,irspec,irspec.gnu                    !writes a gnuplot file to plot an IR
prtfc=1

Hari



More information about the Molpro-user mailing list