ARC could not determine the correct structure when two dihedrals should be changed

AIBN is a radical initiator

ARC oscillated between two structures, both have a rotor (the central N-N rotor) with a more stable conformer



Levels used:

Using default level wb97xd/6-311++g(d,p) for geometry optimizations
Using default level wb97xd/6-311++g(d,p) for frequency calculations
Using b3lyp/6-311+g(3df,2p) for single point calculations
Using wb97xd/6-311++g(d,p) for rotor scans

The correct structure of AIBN is:

N       0.43620300   -0.16213600    0.39977000
N      -0.43609600    0.16200900   -0.39967300
N       3.47047000   -1.53123100    0.03196200
N      -3.46996200    1.53150000   -0.03036300
C       1.77826200    0.47460500    0.12212700
C      -1.77820800   -0.47465200   -0.12199900
C       2.06997600    1.34762500    1.36001200
C       1.86126100    1.27708200   -1.18253100
C      -1.86100900   -1.27778400    1.18227200
C      -2.07041800   -1.34697300   -1.36024900
C       2.72158400   -0.65672400    0.08094100
C      -2.72128800    0.65684600   -0.07998100
H       3.08053300    1.75482400    1.30309300
H       1.97462700    0.76131600    2.27429700
H       1.35568300    2.17301000    1.39068400
H       1.63043300    0.65189300   -2.04518700
H       2.86999700    1.67776300   -1.29694300
H       1.14801100    2.10104700   -1.15797500
H      -1.14806900   -2.10199900    1.15698900
H      -2.86984100   -1.67817400    1.29685000
H      -1.62961800   -0.65314800    2.04517300
H      -1.35626800   -2.17245900   -1.39156500
H      -3.08102200   -1.75404500   -1.30325100
H      -1.97523500   -0.76020200   -2.27425500

Reproduce the AIBN case using the listed optimization, frequency, single-point, and rotor-scan levels and the supplied coordinates. Start by tracing the rotor-scan and conformer-selection entry points; done means the calculation no longer oscillates between structures and selects the reported correct structure.