Invalid number of roots!

Dear MRCC community,

I tried to make some very simple geometry optimizations using CCSDT and I got a strange error for HS ad HO which I did not get for the closed shell HCl.

The error is as follows

Energy of reference determinant [au]: -75.391440109426
Length of property integral file (Mbytes): 2.7
Property value for ref. det., X-DIP: 0.000000000000
Sorting integrals...
Property value for ref. det., Y-DIP: 0.000000000000
Sorting integrals...
Property value for ref. det., Z-DIP: 0.722373733323
Sorting integrals...
Calculation of diagonal elements of Hamiltonian...
Invalid number of roots!

Fatal error in exec mrcc.
Program will stop.


The input file is quite simple, but I wonder if I committed some mistake. Here it is for HO (the same problem occurs with HS)

# CCSDT calculation for HO with cc-pCVDZ basis set
basis=cc-pCVDZ
calc=CCSDT
mem=16GB
gopt=full
# freq=on
# pressure=101325

HO molecule with cc-pVDZ

unit=bohr
mult=2
core=corr
geom
O
H 1 R1

R1 = 2.065149


If anyone can help I will be grateful.

Oscar

Dear Oscar,
The occupation changes in the second iteration, and the CC program cannot restart from the previous step. Please specify the occupation, which is always recommended for open shell species:
occ=3,1,1,0/3,0,1,0