[molpro-user] FW: Chirgwin-Coulson weights of structures

[Jarowski Peter Damian]

Dear All:

I am running some fully variational CASVB calculations using an MCSCF wavefunction to start. The VB input part is below. 

---
{multi,maxit=60;
OCC,36;
CLOSED,26;
WF,62,1,0;
{vb; VBWEIGHTS,ALL}
}
---

This is a single configuration calculation with 42 structures being calculated in a 10,10 active space. The output weights are printed below. (The Lowdin weights just read NAF, but we can try to fix this later)

---
Chirgwin-Coulson weights of structures :
  - - - - - - - - - - - - - - - - - - - -
 VB spin+space (norm   1.00000000) :
   0.00001672 -0.04608597 -0.02870133  0.00000356  0.00000916  0.00183649
   0.00090114  0.00000348  0.00000582  0.00000122 -0.00435596 -0.02824020
  -0.00191792 -0.00938404  0.00606801  0.00329913  0.00000620  0.00000029
   0.00000124 -0.02907838 -0.00656249 -0.00965980 -0.00208033  0.00000213
  -0.00555630 -0.00711871 -0.00191982 -0.00253644  0.32349132  0.19443701
   0.00000015  0.00000000  0.00000058  0.07958292  0.20037193  0.02619681
   0.06613749 -0.00000004  0.16173021  0.04823671  0.05452044  0.01633756
  VB spin only  (norm   0.60422402) :
   0.00002588  0.01252354  0.00816952  0.00000942  0.00002324  0.00022804
   0.00009489  0.00000532  0.00001104  0.00000529  0.00067276  0.01070701
   0.00040694  0.00354436  0.00125180  0.00063778  0.00001294  0.00000229
   0.00000516  0.01073770  0.00559881  0.00356439  0.00159714  0.00000360
   0.00321263  0.00162584  0.00117738  0.00063395  0.23409530  0.14141822
   0.00000196  0.00000964  0.00001202  0.07945705  0.17651152  0.02586927
   0.05783162  0.00000025  0.12772344  0.03495132  0.04357542  0.01205432
----

After much googling and looking through manuals, I am unable to find a description of the structure weight output. One can see the structures and their weights, but there is no information about what these weights physically refer to, i.e. what resonance structure. Other programs like VB2000 or XMVB list the positions of the electrons. Could anyone please direct me to the appropriate source to match these values to their resonance structures. Your help would be much appreciated.

Dr. Peter D. Jarowski