 Early theoretical studies of ScH3 revealed that the molecule is unstable, the bulk substance is likely to be a colourless gas with a low activation energy toward the conversion into trimeric clusters due to the electron deficient nature of the monomer, not unlike the group 13 hydrides.One major difference, is that the dimer is the most stable cluster for group 13 hydrides.This can be attributed to the distortion caused by the "d"-orbitals.