asSym is (for molecules with a centre of inversion) the symmetry of the rovibronic wavefunction: 'a' or 's' such that the total wavefunction including nuclear spin is symmetric or antisymmetric with respect to permutation of identical nuclei (P12), according to whether they are bosons or fermions respectively.
ElecStateLabel is a label identifying the electronic state: X, A, a, B, etc.
F is the quantum number associated with the total angular momentum including nuclear spin: F = J + I1 if only one hyperfine coupling is resolved, F = F1 + I2 if two couplings are resolved, or F = F2 + I3 if all three couplings are resolved.
F1 is the intermediate angular momentum quantum number associated with the coupling of the rotational angular momentum and nuclear spin of nucleus 1 where two or three such couplings are resolved: F1 = J + I1; F1 is often not a good quantum number.
F2 is the intermediate angular momentum quantum number associated with the coupling of the rotational angular momentum and nuclear spin of nucleus 2 where three such couplings are resolved: F2 = F1 + I2; F2 is often not a good quantum number.
I is a nuclear spin quantum number corresponding to the coupling of the nuclear spin angular momenta of two identical nuclei, I = I1 + I2.
J is the quantum number associated with the total angular momentum excluding nuclear spin, J.
kronigParity is the 'rotationless' parity: the parity of the total molecular wavefunction excluding nuclear spin and rotation with respect to inversion through the molecular centre of mass of all particles' coordinates in the laboratory coordinate system. For integer J, total parity is +(-1)J for 'e' states and -(-1)J for 'f' states.
l2 is the vibrational angular momentum quantum number associated with the degenerate bending vibration, ν2; positive and negative values distinguish l–type doubling components.
parity is the total parity: the parity of the total molecular wavefunction (excluding nuclear spin) with respect to inversion through the molecular centre of mass of all particles' coordinates in the laboratory coordinate system, the E* operation.
r is a named, positive integer label identifying the state if no other good quantum numbers or symmetries are known.
v1 is the vibrational quantum number associated with the ν1 normal mode.
v2 is the vibrational quantum number associated with the doubly-degenerate ν2 normal mode.
v3 is the vibrational quantum number associated with the ν3 normal mode.