Molecule Types Vibrational Structure <Prev Next>

Vibrational Mode

One of these items will be present for each vibrational mode under each electronic state. The number is controlled by the nModes at the molecule level.

Settings

Symmetry Symmetry of this vibrational mode. Note that this setting is shared with every state in the molecule.
vMin Minimum vibrational quantum number for this mode to include in the basis. Note that an implementation restriction in the current version means that values of vMin > 0 are likely to slow calculations for intensities considerably.
vMax Maximum vibrational quantum number for this mode to include in the basis

Parameters

Omega Vibrational Frequency
xOmega Anharmonic terms. Diagonal vibrational energy is taken as:
Omega(v+d/2) + xOmega(v+d/2)2 + yOmega(v+d/2)3 + zOmega(v+d/2)4 + gll2
where d is the degeneracy of the mode. Note the sign of xOmega - this is often taken as negative in the Dunham expansion for diatomic molecules. For polyatomic molecules, xOmega is typically written as xii, yOmega as xiii and zOmega as xiiii. For terms involving more than one mode, like x12 add a Vibrational Perturbation.
yOmega
zOmega
gll
epsOmega Renner-Teller term
lx0
l matrix elements for first nucleus for this vibrational mode in units of 1/sqrt(amu). Repeated  for each nucleus, or absent if the l matrix is not being used to calculate Franck-Condon factors
ly0
lz0
...

Operations

Right click on the item in the constants window for the following operations in addition to the standard ones:

Sort Sort modes into standard order, i.e. Symmetry and then descending order of frequency. Note that this option re-orders the modes in every state of the molecule.
Global Shift Up Shift this mode up in every state in the molecule. Note that the "Move Up" item on the same menu only moves the values up for the selected state.
Global Shift Down
 Shift this mode down in every state in the molecule. Note that the "Move Up" item on the same menu only moves the values up for the selected state