Dynamics of Semiflexible Chains, Stars, and Dendrimers

Abstract

Focusing on mechanical and dielectric relaxation, we study the dynamics of semiflexible linear chains, stars, and dendrimers. For this, we use an extension of the Rouse-model in which we include, in the spirit of Bixon and Zwanzig ( J. Chem. Phys. 1978, 68, 1896 and of von Ferber and Blumen ( J. Chem. Phys. 2002, 116, 8616), restrictions on the bonds' orientations. In every case the dynamical matrix in the bonds' representation turns out to be a sparse matrix, a fact which simplifies its diagonalization and may pave the way for further analytical treatments.

Relaxation Dynamics of Semiflexible Fractal Macromolecules

“…Since one variable is sufficient to describe the opposing movement of two Z (1) branches, one obtains a single equation of motion (36). Hence, the corresponding coefficient matrix reads:…”

“…The response function to this harmonic strain is the complex shear modulus G * (ω) = G (ω) + iG (ω) (see [46]), consisting of the storage modulus G (ω) and the loss modulus G (ω). The analytical expressions of the two moduli expressed in the reduced variables that are obtained by dividing the moduli by νk B T are given by [27,36]:…”

Maximal entropy random walk improves efficiency of trapping in dendrimers

“…Their unique structural features make them promising candidates for a broad range of potential applications such as light harvesting antennae 3,4 and molecular amplifiers 5,6 , the latter of which can be used as efficient platforms for drug delivery 7 . In view of their practical significance, thus far, dendrimers have received extensive attention within the scientific community [8][9][10][11][12][13][14][15][16] . In the context of light harvesting by dendrimers, it is the large number of absorbing elements at the periphery and an efficient transfer of the absorbed energy to the center that make dendrimers work as antennas 17 .…”

Semiflexibility Highlights the Polymers' Topology: Monte Carlo Studies

“…While recent analytical extensions of the generalized Gaussian structures picture (GGS) [1] to the case of semiflexible branched polymers [2][3][4][5] and rings [5,6] give qualitative clues to the behavior of polymers, numerical simulation techniques allow to investigate the role of the excluded volume and thus provide a more realistic approach. For this we present here a simulation study of different topological structures by means of the bond fluctuation model (BFM), [7,8] which allows to account both for branching and/or presence of loops and also for semiflexible behavior.…”

“…In the analysis of our results we focus on the mean square radius of gyration (as a general static property of polymers) and on the bond vector correlation function (as an example of local properties). We compare the simulation data with the theoretical predictions based on the extended GGS approach [2][3][4] and on the maximum-entropy principle (MEP). [5,6] Now, a theoretical approach which was recently shown to be very well suitable for the description of semiflexible tree-like polymers (STPs) as well as of semiflexible rings is the MEP.…”