Hund's case (a) diatomics

ElecStateLabel

XML Element

hunda:ElecStateLabel

Description

ElecStateLabel is a label identifying the electronic state: X, A, a, B, etc..

Attributes

None

Restrictions

string

elecInv

XML Element

hunda:elecInv

Description

elecInv is the parity of the electronic wavefunction with respect to inversion through the molecular centre of mass in the molecular coordinate system.

Attributes

None

Restrictions

'g' or 'u'

elecRefl

XML Element

hunda:elecRefl

Description

elecRefl is the parity of the electronic wavefunction with respect to reflection in a plane containing the molecular symmetry axis in the molecular coordinate system (equivalent to inversion through the molecular centre of mass in the laboratory coordinate system).

Attributes

None

Restrictions

'+' or '-'

|Λ|

XML Element

hunda:Lambda

Description

|Λ| is the quantum number associated with the magnitude of the projection of the total electronic orbital angular momentum, L, onto the molecular axis.

Attributes

None

Restrictions

non-negative integer

|Σ|

XML Element

hunda:Sigma

Description

|Σ| is the quantum number associated with the magnitude of the projection of S onto the molecular axis.

Attributes

None

Restrictions

non-negative integer or half-odd integer; |Σ| = S, S-1, ..., 0.5 or 0

Ω

XML Element

hunda:Omega

Description

Ω is the quantum number associated with the projection of the total angular momentum (excluding nuclear spin), J, onto the molecular axis: Ω = |Λ + Σ| (or Ω = |Λ| + Σ if S > |Λ| > 0).

Attributes

None

Restrictions

non-negative integer or half-integer; |Ω| ≤ J

S

XML Element

hunda:S

Description

S is the quantum number associated with the total electronic spin angular momentum, S.

Attributes

None

Restrictions

non-negative integer or half-odd integer

v

XML Element

hunda:v

Description

v is the vibrational quantum number.

Attributes

None

Restrictions

non-negative integer

J

XML Element

hunda:J

Description

J is the quantum number associated with the total angular momentum excluding nuclear spin: J = L + S + R.

Attributes

None

Restrictions

non-negative integer or half-odd integer

F1

XML Element

hunda:F1

Description

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 such couplings are resolved: F1 = J + I1; F1 is often not a good quantum number.

Attributes

nuclearSpinRef: a label identifying the nuclear spin coupled to J to form the intermediate angular momentum

Restrictions

non-negative integer or half-integer; |J - I1| ≤ F1 ≤ J + I1

F

XML Element

hunda:F

Description

F is the quantum number associated with the total angular momentum including nuclear spin: F = J + I1 if only one such coupling is resolved, F = F1 + I2 if both couplings are resolved.

Attributes

nuclearSpinRef: a label identifying the nuclear spin coupled to J (or F1) to form the total angular momentum

Restrictions

non-negative integer or half-integer

r

XML Element

hunda:r

Description

r is a named, positive integer label identifying the state if no other good quantum numbers or symmetries are known.

Attributes

name: a string identifying this ranking index

Restrictions

positive integer

parity

XML Element

hunda:parity

Description

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.

Attributes

None

Restrictions

'+' or '-'

kronigParity

XML Element

hunda:kronigParity

Description

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.

Attributes

None

Restrictions

'e' or 'f'

asSym

XML Element

hunda:asSym

Description

asSym is (for diatomic 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 the identical nuclei (P12), according to whether they are bosons or fermions respectively.

Attributes

None

Restrictions

's' or 'a'