Molecule Types Linear Molecules | <Prev Next> |

This contains the rotational
constants and other information specific to each state within a
linear molecule. Note that PGOPHER
will calculate Hund's cases (a) and (b) exactly. Other cases can
be handled, but typically require more work to set up. For Hund's
case (c), for example it may make sense to treat the various
components of a state separately, which is possible by setting up
multiple copies of the state and making use of the OmegaSelect and/or ParitySelect settings.
For example the two halves of a ^{2}Π state can be
treated separately by setting up two ^{2}Π states, one
with OmegaSelect =
½ and one with OmegaSelect
= 3/2.

Colour | Colour - set to "None" to take value from elsewhere as explained in Determining Colours and J ranges. |

RveSelect |
Only include given rovibronic symmetry - for normal use set to 'all' |

S | Electron Spin |

Lambda | Electronic angular momentum - use Sigma-, Sigma+, Pi, Delta, Phi, Gamma, H, I or a numerical value |

gerade | True for gerade (g) states, false for ungerade (u) states;
ignored if the molecule is not symmetric as specified by the
Symmetric
setting for the molecule. |

OmegaSelect | Set to all for normal use; set to a specific
value to restrict the basis states to a specific value of
Ω. Basis states with other values of Ω are
deleted, which will typically change calculated energies.
(If you just want to display selected transitions, use the transitions window.) Note
that if OmegaSelect
is used the F1/F2/F3 numbering and N assignment may
not be consistent, particularly for versions before 8.0.326.
This is because of the algorithm used to determine if the
state is regular or inverted; the OmegaOrder
setting below can be used to force the desired order. |

OmegaOrder |
This is only used in assigning N,
Ω and F1/F2/F3 quantum numbers to final states, and
the default (Auto) is sufficient for all but rather
unusual calculations. Possible values are Auto
(the default), Regular (implying energies are
expected to increase with Ω) and Inverted
(energies decrease with Ω). The algorithm for
assigning quantum numbers assumes energies increase with N
and F number, so this controls how Ω is matched to
these. In addition, if LimitSearch
is set (the default), the expected energy ordering is used
to assign the quantum numbers. See the discussion of F_{n}
in State Settings for more
information. |

Origin | State Origin. | |

Width | Linewidth (rotation independent) for state. | |

B | Rotational constant. | Rotation |

A | Spin-orbit coupling constant. | Spin-Orbit |

LambdaSS | Spin - spin coupling constant, λ (=1.5*ε). | Spin-Spin |

o | Spin-spin coupling constant giving lambda doubling for Omega = 0 states. | Λ Doubling |

theta | Higher Order Spin-Spin interaction (S>=2 only). | Spin-Spin |

Gamma | Spin rotation coupling constant. | Spin-Rotation |

p | Lambda doubling constant. | Λ Doubling |

q | Lambda doubling constant. | Λ Doubling |

D | Quartic centrifugal distortion. | Rotation |

H | Sextic centrifugal distortion. | Rotation |

L | J^{8}
centrifugal distortion. |
Rotation |

M | J^{10}
centrifugal distortion. |
Rotation |

PP | J^{12}
centrifugal distortion. (Not P to avoid confusion with p.) |
Rotation |

AD | Centrifugal distortion of A. |
Spin-Orbit |

LambdaD | Centrifugal Distortion of λ. | Spin-Spin |

LambdaH | J^{4}
Centrifugal Distortion of λ. |
Spin-Spin |

oD | Centrifugal distortion of o for Π states. n
for Δ states. |
Λ Doubling |

oH | J^{4}
Centrifugal distortion of o for Π states. o
for Δ states. |
Λ Doubling |

oL | J^{6}
Centrifugal distortion of o for Π states only. |
Λ Doubling |

pD | Centrifugal distortion of p for Π states only. |
Λ Doubling |

pH | J^{6}
Centrifugal distortion of p for Π states only. |
Λ Doubling |

pL | J^{8}
Centrifugal distortion of p for Π states only. |
Λ Doubling |

qD | Centrifugal distortion of q for Π states only. |
Λ Doubling |

qH | J^{6}
Centrifugal distortion of q for Π states only. |
Λ Doubling |

qL | J^{8}
Centrifugal distortion of q for Π states only. |
Λ Doubling |

gammaD | Centrifugal distortion of gamma. | Spin-Rotation |

gammaH | J^{6}
Centrifugal distortion of gamma. |
Spin-Rotation |

gammaL | J^{8}
Centrifugal distortion of gamma. |
Spin-Rotation |

eta |
Additional spin orbit term for quartet and higher states | Spin-Orbit |

gammaS |
Additional spin rotation term for quartet and higher states | Spin-Orbit |