4. ltcs: Closed-shell, linear triatomic molecules

ElecStateLabel

Description

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

XML element

ltcs:ElecStateLabel

Attributes

None.

Restrictions

  • string

v1

Description

v1 is the vibrational quantum number associated with the ν1 normal mode.

XML element

ltcs:v1

Attributes

None.

Restrictions

  • non-negative integer

v2

Description

v2 is the vibrational quantum number associated with the doubly-degenerate ν2 normal mode.

XML element

ltcs:v2

Attributes

None.

Restrictions

  • non-negative integer

l2

Description

l2 is the vibrational angular momentum quantum number associated with the degenerate bending vibration, ν2; positive and negative values distinguish l–type doubling components.

XML element

ltcs:l2

Attributes

None.

Restrictions

  • integer
  • |l2| = v2v2-2, ..., 1 or 0

v3

Description

v3 is the vibrational quantum number associated with the ν3 normal mode.

XML element

ltcs:v3

Attributes

None.

Restrictions

  • non-negative integer

J

Description

J is the quantum number associated with the total angular momentum excluding nuclear spin, J.

XML element

ltcs:J

Attributes

None.

Restrictions

  • non-negative integer

I

Description

I is a nuclear spin quantum number corresponding to the coupling of the nuclear spin angular momenta of two identical nuclei, I = I1 + I2.

XML element

ltcs:I

Attributes

  • nuclearSpinRef: a whitespace delimited list of labels identifying the nuclear spins coupled to form I
  • id: a label identifying the nuclear spin angular momentum, I, formed by this coupling

Restrictions

  • non-negative integer or half-integer

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

XML element

ltcs:F1

Attributes

  • nuclearSpinRef: a label identifying the nuclear spin coupled to J to form the intermediate coupled angular momentum quantum number, F1

Restrictions

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

F2

Description

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.

XML element

ltcs:F2

Attributes

  • nuclearSpinRef: a label identifying the nuclear spin coupled to F1 to form the intermediate angular momentum

Restrictions

  • non-negative integer or half-integer
  • |F1 - I2| ≤ F2 ≤ F1 + I2

F

Description

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.

XML element

ltcs:F

Attributes

  • nuclearSpinRef: a label identifying the nuclear spin coupled to J, F1, or F2 to form the total angular momentum

Restrictions

  • non-negative integer or half-integer
  • |F2 - I3| ≤ F ≤ F2 + I3

r

Description

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

XML element

ltcs:r

Attributes

name: a string identifying this ranking index

Restrictions

  • positive integer

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.

XML element

ltcs:parity

Attributes

None.

Restrictions

  • '+' or '-'

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. For integer J, total parity is +(-1)J for 'e' states and -(-1)J for 'f' states.

XML element

ltcs:kronigParity

Attributes

None.

Restrictions

  • 'e' or 'f'

asSym

Description

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.

XML element

ltcs:asSym

Attributes

None.

Restrictions

  • 's' or 'a'