Symbols used to identify irreducible representations of groups: A = singly degenerate state which is symmetric with respect to rotation about the principal C_n axis, B = singly degenerate state which is antisymmetric with respect to rotation about the principal C_n axis, E = doubly degenerate, T = triply degenerate, X_g = (gerade, symmetric) the sign of the wavefunction does not change on inversion through the center of the atom,

character table | group theory | irreducible representation