https://doi.org/10.1140/epjb/e2010-00155-9
Thermodynamics of the rupture in a Morse lattice
1
Emanuel Institute of Biochemical Physics, Russian Academy of
Sciences, ul. Kosygina 4, 119334 Moscow, Russian Federation
2
Institut für Physik, Humboldt-Universität Berlin, Newtonstrasse 15, 12489 Berlin, Germany
3
Instituto Pluridisciplinar, Universidad Complutense de Madrid, Paseo Juan XXIII, 1, 28040 Madrid, Spain
Corresponding author: a gvin@deom.chph.ras.ru
Received:
20
December
2009
Revised:
11
March
2010
Published online:
19
May
2010
The rupture of a Morse lattice is considered in the present
paper. The critical rupture force Fcr is found to
decrease with the number of particles N as Fcr ~ 1/
. The partition function is obtained for two states of
the lattice – with all equal bond lengths and one broken bond.
In the first case an accurate expressions for thermodynamic
parameters are obtained, and thermodynamic expressions are
derived in the harmonic approximation in the latter case. The
analytical predictions are confirmed by extensive MD simulations.
Cis-trans isomerization is considered as an example. Volume
fractions of trans- and cis-isomers versus number of
monomer units N are found depending on the torsion stiffnesses.
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2010
