Ae. Kondo et Wj. Meath, ON THE SPECTRAL AND DYNAMIC EFFECTS OF NEAR-NODAL MOLECULE EMF COUPLING ARISING FROM PERMANENT DIPOLE-MOMENTS, Molecular physics, 92(5), 1997, pp. 805-812
The spectral and temporal consequences of a non-zero difference d(kj)
= mu(kk) - mu(jj) between the permanent dipole moments mu(jj) of two s
tates involved in a transition are investigated for two-and three-leve
l model molecular systems interacting with a continuous wave laser. Th
e field strengths are such that the molecule-EMF couplings for the sys
tems are near-nodal. The interesting spectral and dynamic effects of n
ear-nodal molecule-EMF couplings are unique to transitions where d(kj)
not equal 0, relative to d(kj) = 0 These effects are studied using ex
act Floquet calculations and analytical solutions in the two-level rot
ating wave approximation (RWA). The RWA discussion of near-nodal molec
ule-EMF couplings, how they are achieved, and their effects, is quite
general and applies to any two-level model of a dipolar molecule. The
actual values of the laser parameters required to achieve a molecule-E
MF coupling node depend on the specific molecule under consideration.
This is illustrated with explicit two-and three-level molecular models
, based on the S-0 and S-1 states of 1-[p-(N,N-dimethyl- amino)phenyl]
-4-(p-nitrophenyl)-1,3-butadiene. Although the held strengths required
to achieve near-nodal couplings are too large for the quantitative ap
plication of the analytical results, the two-level RWA solutions are c
rucial for the qualitative interpretation and prediction of the exact
laser-molecule behaviour. The examples illustrate that the near-nodal
effects of d(kj) not equal 0, as predicted by the two-level RWA and ve
rified by the two-and three-level exact calculations, persist when nei
ghbouring energy levels are present in the model.