Molecule Types Linear Molecules <Prev Next>

Linear Molecule Nucleus

If the parent molecule has nNuclei non zero, then each state will have nNuclei LinearNucleus objects. (In principle the Spin and AsNext properties should be set at the molecule level, but in fact have been implemented at the state level, and any change in these two properties is copied to all the states in the molecule.) The following coupling scheme is normally used:
F1 = J1 + I1; F2 = F1 + I2; ... F = Fn-1 + In
though at alternative scheme must be used for equivalent nuclei, as described under the AsNext setting. Note that only nuclei not explicitly simulated should be included in calculating the SymWt and AsymWt statistical weights.

Settings

Spin Nuclear spin.
AsNext Set to indicate that this nucleus is equivalent to the following nucleus. This is required for molecules with a centre of symmetry, where nuclei not on the centre of symmetry must occur as equivalent pairs. In these circumstances all parameters are taken from the second of the two nuclei, and the modified coupling scheme:
I12 = I1 + I2; F = J + I12
is used.
This setting can also be used for molecules without a centre of symmetry, in which case the alternate coupling scheme is used but the nuclei are not forced, or even required, to be identical.

Parameters

a Nuclear spin - orbit interaction (I.L).
b Nuclear spin - electron spin (I.S). Note that b = bF - c/3.
c Nuclear spin - electron spin dipole dipole interaction diagonal in Lambda.
d Nuclear spin - electron spin dipole dipole interaction off diagonal in Lambda by 2.
eQq0 Nuclear quadrupole coupling constant diagonal in Lambda.
eQq2 Nuclear quadrupole coupling constant off diagonal in Lambda by 2.
cI Nuclear spin rotation (I.J).
aJ Centrifugal distortion of nuclear spin - orbit interaction (I.L). (Outline implementation)
bJ Centrifugal distortion of nuclear spin - electron spin (I.S). (Outline implementation)
cJ Centrifugal distortion of nuclear spin - electron spin dipole dipole interaction diagonal in Lambda. (Outline implementation)
dJ Centrifugal distortion of nuclear spin - electron spin dipole dipole interaction off diagonal in Lambda by 2. (Outline implementation)
eQq0J Centrifugal distortion of nuclear quadrupole coupling constant diagonal in Lambda. (Outline implementation)
eQq2J Centrifugal distortion of nuclear quadrupole coupling constant off diagonal in Lambda by 2. (Outline implementation)