Eugene S. Kryachko

Collective proton transfer in the (AH…)∞ system with double-Morse symmetric potential. I. Model of proton kink defect

Abstract Formation of a proton defect in an infinite one-dimensional hydrogen-bonded chain (Aue5f8H…) ∞ , described by the symmetric double-Morse potential, is studied within the continuum approach. The explicit solution for the proton kink defect is obtained at fixed A⋯A separations. The expression which describes the behavior of the relaxed heavier A subsystem under formation of proton kink, is derived explicitly with the first-order adiabatic treatment.

Study of tunnelling in symmetrical double-Morse hydrogen bonds via the instanton-soliton approach: large polarizability and isotopic effect

Abstract An explicit expression for the energy splitting due to tunnelling in a symmetric double-Morse potential was derived within the instanton-soliton approach to Feynmans path integral formalism and to first order with regard to Plancks constant. Different formulae for the energy splitting in terms of the dissociation constant, the barrier height, the barrier thickness, and the classical frequency of the transition state are also presented. The formula obtained was applied to study the concept of large proton polarizability and the large isotopic effect of proton tunnelling in symmetrical homoconjugated hydrogen bonds.

Ab initio study of L-orientational defect in the hydrogen-bonded pattern of liquid water

Abstract Current status of the theory of orientational defects in H-bonded pattern of liquid water is briefly reviewed. Ab initio calculated water clusters from dimer to heptamer are thoroughly analyzed in terms of H-bonded pattern. New water heptamer structure of norbornane type is found via ab initio HF 6-311G∗∗ calculation. Its normal vibrations are properly assigned. Two ab initio water hexamers that refer to orientational defects are revealed. This is the first evidence of ab initio orientational defect in H-bonded patterns of water clusters. Some properties including normal vibrations of these defects, are studied.

On the theory of the dynamics of hydrogen bonds coupled with a bath. Part I

Abstract Three topics in the theory of H-bonding are under investigation. The first one is tunneling treated within a two-level state model. The second topic concerns time-dependent aspects, particularly, a propagation of the initial state of the system coupled to a single mode evolving in time. In this regard, a harmonic oscillator coupled anharmonically to such a mode is analyzed. The third topic is dedicated to the study of the dynamics of a weak H-bond embedded in an inert heat bath that behaves stochastically. Spectroscopic aspects of this stochastic model are thoroughly discussed within the linear response theory.

Soliton model for collective proton transfer in extended realistic hydrogen-bonded systems

The discretized version of the collective proton transfer in extended one-dimensional hydrogen-bonded systems with the Lippincott-Schroeder potential is studied. A discrete quasi-kink is compared with its continuum approximation ‘image’. The Peierls-Nabarro activation energy of diffusion of collective proton defect is estimated. The concept of local proton potentials is introduced on the background of the kink-carrier collective variable.

THE CONCEPT OF SOLITON-CARRIER COLLECTIVE VARIABLE FOR PROTON TRANSFER IN EXTENDED HYDROGEN-BONDED SYSTEMS: OVERVIEW

It seems now to be the right time to take a overlook at the application of the concept of soliton1,2 in the theory of hydrogen bonding, and the theory of anomalous proton conductivity in liquid water and ice particularly. The important progress continues to be made in this area at a substantial pace. The hot example is just these Proceedings. A number of problems which are nearly as old as the object under study itself (e.g., liquid water) remains open, and the new problems continue to arise and develop. On the other hand, this area is now about ten years old, and already many problems have been solved and the key to the general theory of proton transfer we guess has been posed.

The model of librational motion in liquid waters

Abstract A theoretical model of libration vibrations in liquid water is proposed within the quantum-mechanical picture of the behaviour of a quantum rigid point dipole of the OH bond of a water molecule in a permanent internal electric field of tetrahedral surroundings.