C. S. G. Phillips Created 2026-10-20 Updated 2026-11-05
C. S. G. Phillips coauthored reference tables connecting molecular symmetry with group theory. Their character tables organize how coordinates, rotations and other molecular quantities transform under a point group, supporting assignments in molecular spectroscopy.[ref]
Tables for Group Theory by P. W. Atkins and others. 2008 tables, printed pp.7,10,12,17: molecular character conventions
M. S. Child Created 2026-10-20 Updated 2026-11-05
M. S. Child coauthored reference tables for applying group theory to molecules. A character table makes the symmetry behaviour of a vibration or electronic function comparable with the irreducible representations of the relevant molecular point group.[ref]
Past exam of the chemistry A course of the University of Cambridge 2024 Paper 1 A4 b iii Solution 2026-10-20
Taking the matrix trace of those matrices givesThe one-dimensional subspace has characters , identifying . The pair has characters , identifying . ThereforeThe dimensions add to three, as required. The pair must be retained together: a ninety-degree improper rotation mixes them, so either one alone is not a complete symmetry basis.[ref]
Past exam of the chemistry A course of the University of Cambridge 2024 Paper 1 A4 c ii Solution 2026-10-20
The highest expected orbital degeneracy is five. Ideal buckminsterfullerene has Ih molecular point group symmetry. Its irreducible orbital representations include five-dimensional and representations; no single-valued orbital irrep has higher dimension.
This counts distinct spatial molecular orbitals. It does not multiply by electron spin, and it excludes accidental coincidences between unrelated irreps. In a real environment, symmetry lowering can split these degeneracies.[ref]