raise Exception in convert_unsaturated_bond_to_biradical
raise Exception in convert_unsaturated_bond_to_biradical

avoids infinite loop when none of the indices could be converted to bonds

nickvandewiele/RMG-Py,nickvandewiele/RMG-Py,nyee/RMG-Py,chatelak/RMG-Py,nyee/RMG-Py,pierrelb/RMG-Py,pierrelb/RMG-Py,chatelak/RMG-Py