Danish Ph.D. School in Nonlinear Science
Sponsored by the Danish Research Academy
Soliton Modelling for Energy and Charge Transport
in Molecular Systems
by A.V. Savin,
Institute for Problems of Physics and Technology,
Moscow, Russia
e-mail:alex@savin.msk.su
presently: as@imm.dtu.dk
and A.V. Zolotaryuk,
Bogolyubov Institute for Theoretical Physics, Kyiv, Ukraine
e-mail: azolo@gluk.apc.org
presently: az@imm.dtu.dk
MIDIT-seminars 394 and 395
Thursday December 11, 1997 15.00 h and 16.00 h
at MIDIT, IMM Building 305, room 027
A.V. Zolotaryuk and A.V. Savin,
I. Polaron models: interaction of a quamtum quasi-particle
with nonlinear lattices
Abstract: A survey on soliton models used to
investigate transfers
of vibrational energy and electrons in molecular chains is given.
These models describe the following three transport mechanisms:
(i) the self-trapping of an excess quantum quasi-particle by the
acoustic and optical modes (Davydov's and Holstein's models),
(ii) Capture and transfer of a quantum quasi-particle by the
lattice (acoustic) soliton, (iii) capture and transport of a quantum
quasi-particle by a topological soliton. Numerical methods for
seeking moving soliton solutions are presented. Applications to
biomolecular dynamics are briefly discussed.
A.V. Savin and A.V. Zolotaryuk,
II. Proton dynamics in hydrogen-bonded networks and
soliton ratchets
Abstract: Applications for a description of the proton
transport in
quasi-one-dimensional hydrogen-bonded chains are presented. A two-component
soliton model for proton transfers in such chains is derived and
treated for the case when heavy ions of the background sublattice are
allowed to move. Peculiar properties of soliton-velocity spectrum
for this case are discussed. The two-dimensional topological solitons
are treated on the basis of the nonlinear dynamical square ice model.
The ratchet soliton motion that occurs in the one-dimensional
kink-bearing family of models with an anisotropic spatial
asymmetry of the on-site potential is also discussed.