Diffusion-controlled rates of formation were found from the temperature dependence of apparent quenching rate constants for exciplexes, when the driving force of excited-state electron transfer -0.1 < deltaG(ET)* < +0.1 eV. This is inconsistent with the conventional mechanism of electron-transfer reactions, involving preliminary reorganisation of the medium and reactants, and provides strong support for the mechanism of medium reorganisation stimulated by strong electronic coupling of locally excited and charge-transfer states.

For the first time, the Holocene history of the Serp-i-Molot tidewater glacier at the eastern side of the Novaya Zemlya archipelago, Kara Sea, has been reconstructed based on AMS 14 C dating and multiproxy analyses (lithology, mineralogy, geochemistry and microfossils) of glaciomarine sediments from the Tsivol'ki Fjord. Three main phases of the Holocene evolution of the fjord environment are identified. During the early phase, c. 10.6 to 4.6 cal. ka BP, the glacier front was located close to the fjord mouth. The middle phase, c. 4.6 to 0.9 cal. ka BP, was characterized by frontal glacier retreat and shallowing of the fjord owing to glacio-isostatic uplift of the North Island of Novaya Zemlya. The late phase, from 0.9AE0.1 cal. ka BP until present, reflects the stabilization of the glacier front in the inner fjord. The absence of major Neoglacial advances of the Serp-i-Molot glacier is explained by the local climate of the Kara Sea and Novaya Zemlya, which prevents the penetration of moist air flow from the North Atlantic.

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The fluorescence decays of several exciplexes with partial charge transfer have been investigated in solvents of various polarity. The measured lifetimes are found to be in reasonable agreement with the activation enthalpy and entropy of exciplex decay obtained earlier from the temperature dependence of the exciplex emission quantum yields. For exciplexes with 9-cyanophenanthrene substantial contribution of the higher local excited state into the exciplex electronic structure is found and borrowed intensity effect enhances the exciplex emission rate constants.