1997 |
|
| 2. | Chakravarty, C; Ramaswamy, R Instantaneous normal mode spectra of quantum clusters Journal Article The Journal of Chemical Physics, 106 (13), pp. 5564–5568, 1997, ISSN: 0021-9606. Abstract | Links | BibTeX | Tags: lenard-jones, Monte Carlo, phase transition @article{Chakravarty1997, title = {Instantaneous normal mode spectra of quantum clusters}, author = {C Chakravarty and R Ramaswamy }, url = {https://pubs.aip.org/aip/jcp/article-pdf/106/13/5564/10783293/5564\_1\_online.pdf}, doi = {10.1063/1.473578}, issn = {0021-9606}, year = {1997}, date = {1997-04-01}, journal = {The Journal of Chemical Physics}, volume = {106}, number = {13}, pages = {5564–5568}, abstract = {The spectrum of instantaneous normal mode (INM) frequencies of finite Lennard-Jones clusters is studied as a function of the extent of quantum delocalization. Configurations are sampled from the equilibrium distribution by a Fourier path integral Monte Carlo procedure. The INM spectra, average force constants and Einstein frequencies are shown to be interesting dynamical markers for the quantum delocalization-induced cluster solid–liquid transition. Comparisons are made with INM spectra of quantum and classical Lennard-Jones liquids. The methodology used here suggests a general strategy to obtain quantal analogs of various classical dynamical quantities}, keywords = {lenard-jones, Monte Carlo, phase transition}, pubstate = {published}, tppubtype = {article} } The spectrum of instantaneous normal mode (INM) frequencies of finite Lennard-Jones clusters is studied as a function of the extent of quantum delocalization. Configurations are sampled from the equilibrium distribution by a Fourier path integral Monte Carlo procedure. The INM spectra, average force constants and Einstein frequencies are shown to be interesting dynamical markers for the quantum delocalization-induced cluster solid–liquid transition. Comparisons are made with INM spectra of quantum and classical Lennard-Jones liquids. The methodology used here suggests a general strategy to obtain quantal analogs of various classical dynamical quantities |
1987 |
|
| 1. | Ramaswamy, R; Barma, M Transport in random networks in a field: Interacting particles Journal Article Journal of Physics A: Mathematical and General, 20 (10), pp. 2973–2987, 1987, ISSN: 03054470. Abstract | Links | BibTeX | Tags: Monte Carlo, Random Network, Random Walk, Transport @article{Ramaswamy1987, title = {Transport in random networks in a field: Interacting particles}, author = {R Ramaswamy and M Barma}, url = {https://ramramaswamy.org/papers/031.pdf}, doi = {10.1088/0305-4470/20/10/039}, issn = {03054470}, year = {1987}, date = {1987-01-01}, journal = {Journal of Physics A: Mathematical and General}, volume = {20}, number = {10}, pages = {2973–2987}, abstract = {Transport through a random medium in an external field is modelled by particles performing biased random walks on the infinite cluster above the percolation threshold. Steps are more likely in the direction of the field-say downward-than against. A particle is allowed to move only onto an empty site (particles interact via hard core exclusion). Branches that predominantly point downwards and backbends-backbone segments on which particles must move upwards-act as traps. The authors have studied the movement of interacting random walkers in branches and backbends by Monte Carlo simulations and also analytically. In the full network, the trap-limited current flows primarily through the part of the backbond composed of paths with the smallest backbends and its magnitude in high fields is estimated. Unlike in the absence of interactions, the drift velocity does not vanish in finite fields. However, it continues to show a non-monotonic dependence on the field over a sizeable range of density and percolation probability.}, keywords = {Monte Carlo, Random Network, Random Walk, Transport}, pubstate = {published}, tppubtype = {article} } Transport through a random medium in an external field is modelled by particles performing biased random walks on the infinite cluster above the percolation threshold. Steps are more likely in the direction of the field-say downward-than against. A particle is allowed to move only onto an empty site (particles interact via hard core exclusion). Branches that predominantly point downwards and backbends-backbone segments on which particles must move upwards-act as traps. The authors have studied the movement of interacting random walkers in branches and backbends by Monte Carlo simulations and also analytically. In the full network, the trap-limited current flows primarily through the part of the backbond composed of paths with the smallest backbends and its magnitude in high fields is estimated. Unlike in the absence of interactions, the drift velocity does not vanish in finite fields. However, it continues to show a non-monotonic dependence on the field over a sizeable range of density and percolation probability. |