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The adsorption behavior of 4-cyanobiphenyl (CNBP) has been investigated by means of surface-enhanced Raman scattering (SERS). CNBP appeared to assume a tilted orientation on silver and gold. The presence of the ring C−H band denoted a rather vertical orientation of the biphenyl ring on Ag and Au. On the other hand, considerable red shifts of the ring-breathing modes with the increase in their bandwidths indicated a substantial π-type interaction between the benzene rings and metal substrates. On gold, the concentration-dependent SERS experiment showed CNBP to have a slightly perpendicular stance at its high surface coverage. The presence of the BH4^- ion in sols was found to affect the adsorption reaction and surface orientation of CNBP. The spectral band analysis based on electromagnetic selection rule indicated that CNBP should have a slightly more vertical orientation on gold than on silver at the concentration of ~10^-4 M.

The predissociation of the 1Σ g v ≥ 10 levels of Li 2 has been observed by pulsed and continuous-wave perturbation-facilitated optical-optical double-resonance spectroscopy (PFOODR). Our ab initio calculation shows that the inner wall of the 1Σ g potential intersects the 1Π g repulsive potential at internuclear distance R = 2.00 A˚. The predissociation is due to a Δ S = 0, ΔΛ = ±1 rotational-electronic interaction with the repulsive 1Π g state.

The predissociation of the 13Σ−gv≥ 10 levels of 7Li2has been observed by pulsed and continuous-wave perturbation-facilitated optical–optical double-resonance spectroscopy (PFOODR). Our ab initiocalculation shows that the inner wall of the 13Σ−gpotential intersects the 13Πgrepulsive potential at internuclear distance R= 2.00 Å. The predissociation is due to a ΔS= 0, ΔΛ = ±1 rotational–electronic interaction with the repulsive 13Πgstate.

The direct collisional energy transfer process Li*(3p) + H2 → Li*(3s) + H2 is investigated under gas cell conditions. In particular, we measured the nonreactive far-wing absorption profile of LiH2 complexes by monitoring the Li(3s) → Li(2p) fluorescence at 812.6 nm. Strong satellite structures are observed at around 700 cm^-1 in the blue wing and 162 cm^-1 in the red wing of the LiH2 profile. The experimental results are in agreement with ab initio theoretical predictions, which showed a strong probability of a diabatic transition making the 3p−3s quenching easy.

Three pigments of the guaiazulene class have been isolated from the gorgonian Calicogorgia granulosa. Structures of these compounds have been determined as guaiazulene, 2,2‘-diguaiazulenylmethane, and a new compound, 2,2‘-biguaiazulenyl, by combined chemical and spectroscopic methods. 2,2‘-Biguaiazulenyl exhibited moderate antimicrobial activity.