Open Shell MBD forces

Questions
#1

Hello,

I am trying to run an forces calculation using this input block:

$molecule
0 2
H 0.00000000 0.00000000 -0.25661586
CL 0.00000000 0.00000000 1.28726458
H 0.00000000 0.00000000 -1.03064872
$end

$rem
 JOBTYPE         force
 METHOD          PBE0
 NO_REORIENT     TRUE
 BASIS           Aug-cc-pvqz
 MBDVDW          MBD_FORCES
 MBDVDW_BETA     8500
 SCF_CONVERGENCE 6
 THRESH          9
 GUI             2
$end

but I am having this error: ±-----------------------------------------+
| Calculate MBD vdW contributions |
±-----------------------------------------+
Custom beta value is 0.85
±-----------------------------------------+
| Calculate Hirshfeld volumes |
±-----------------------------------------+
Requested basis set is aug-cc-pVQZ
There are 14 shells and 46 basis functions
A cutoff of 1.0D-09 yielded 105 shell pairs
There are 1165 function pairs ( 1687 Cartesian)
Requested basis set is aug-cc-pVQZ
There are 22 shells and 84 basis functions
A cutoff of 1.0D-09 yielded 253 shell pairs
There are 3763 function pairs ( 6418 Cartesian)
Requested basis set is aug-cc-pVQZ
There are 14 shells and 46 basis functions
A cutoff of 1.0D-09 yielded 105 shell pairs
There are 1165 function pairs ( 1687 Cartesian)
Requested basis set is aug-cc-pVQZ
There are 50 shells and 176 basis functions
A cutoff of 1.0D-09 yielded 1265 shell pairs
There are 15907 function pairs ( 24773 Cartesian)

Q-Chem fatal error occurred in module libvdw/hirshfeld_volume_gradient.C, line 58:

Unrestricted calculations not tested

Please submit a crash report at Q-Chem Crash Reporter
Is it not possible to compute MBD forces for an open shell? Or it’s another problem?

thanks in advance.

#2

This appears to be a limitation of the current implementation of MBD, as a similar closed-shell example runs just fine.

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