In search of triplet ground state GeCNX germylenes (XÂ =Â H, F, Cl, and Br): An ab initio and DFT study

Two triplet germylenes 2t-H and 3t-H appear more stable than their corresponding singlet states. This is found through the comparison of singlet-triplet energy splittings for 24 GeCNX germylenes at 10 levels of theory (X = H, F, Cl, and Br).