[molpro-user] Error in CASPT2 optimization

[Lu Ruifeng]

molpro-userDear molpro users,

When I run an O2 molecule CASPT2 optimization in order to duplicate the results of Keiji Morokuma et al.( J. Chem. Phy. 123,204319(2005)), I am encountering an error adopting an active space of 8e/6o,I can get the right result adopting an active space of 12e/8o. The error occur in output file is as shown:
*********************
 STARTING GEOMETRY OPTIMIZATION FOR RS2                             

 CONVERGENCE THRESHOLDS: 0.300D-03 (STEP) 0.300D-03 (GRADIENT) 0.100D-05 (ENERGY)
 MAX. NUMBER OF STEPS:          50

 *** Long output written to logfile /home/rflu/molpro/o2/sig3.log ***


 Incrementing variable O2O1   by +/- 0.005 ANG
 CURRENT STACK:      CIPRO  MAIN
*********************


My input is given below:
*********************
***,test(o2)
O2O1=1.20752 ang
geometry={x,y;
          o1;
          o2,o1,O2O1}                
basis=6-31+G(d)
int
hf
 
casscf;occ,6,2,2;closed,4;wf,16,4,2;       
rs2;occ,6,2,2;closed,4;wf,16,4,2; 
optg !,MAXIT=200                      
show,O2O1
---
**********************

Can anyone suggest what might be happening here?
   Thanking you in advance
   With bet regards

                  Lu RF 				

　　　　　　　　
　　　　　　　　rflu at dicp.ac.cn
　　　　　　　　　　2006-03-31
　　　　　　　　rflu at dicp.ac.cn
　　　　　　　　　　2006-03-31
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