Publications

@article{Ramaswamy1981y,
title = {Classical methods in molecular scattering: A continuous quantization procedure },
author = {Ramakrishna Ramaswamy and Andrew E DePristo},
url = {https://ramramaswamy.org/papers/012.pdf},
year = {1981},
date = {1981-01-01},
journal = {Chem. Phys. Lett.},
volume = {77},
number = {1},
pages = {190-194},
keywords = {Quantization, Scattering},
pubstate = {published},
tppubtype = {article}
}

@article{Ramaswamy1981x,
title = {Continuous quantization procedure in quasiclassical scattering: Application to atom-Morse oscillator collisions},
author = {Ramakrishna Ramaswamy},
url = {https://ramramaswamy.org/papers/015.pdf},
year = {1981},
date = {1981-01-01},
journal = {Pramana},
volume = {16},
number = {2},
pages = {139-146},
keywords = {Quantization, Scattering},
pubstate = {published},
tppubtype = {article}
}

@article{DePristo1979,
title = {Quantum number and energy scaling for non-reactive collisions},
author = {A E DePristo, S D Augustin, R Ramaswamy and H Rabitz
},
url = {https://doi.org/10.1063/1.438376},
doi = {10.1063/1.438376},
issn = {0021-9606},
year = {1979},
date = {1979-07-15},
journal = {The Journal of Chemical Physics},
volume = {71},
number = {2},
pages = {850-865},
abstract = {Two new theoretical developments are presented in this article. First an energy corrected sudden (ECS) approximation is derived by explicitly incorporating both the internal energy level spacing and the finite collision duration into the sudden S‐matrix. An application of this ECS approximation to the calculation of rotationally inelastic cross sections is shown to yield accurate results for the H+–CN system. Second, a quantum number and energy scaling relationship for nonreactive S‐matrix elements is derived based on the ECS method. A few detailed illustrations are presented and scaling predictions are compared to exact results for R–T, V–T, and V–R, T processes in various atom–molecule systems. The agreement is uniformly very good — even when the sudden approximation is inaccurate. An important result occurs in the analysis of V–T processes: the effects of anharmonic wave functions (coupling) and decreasing vibrational energy gaps (energetics) are separated. Each factor makes significant contributions to the deviation of the anharmonic from the harmonic scaling relationship.},
keywords = {Scattering},
pubstate = {published},
tppubtype = {article}
}

@article{Green1978,
title = {Collisional excitation of interstellar molecules: H2},
author = {S Green, R Ramaswamy and H Rabitz
},
url = {https://ui.adsabs.harvard.edu/abs/1978ApJS…36..483G},
doi = {10.1086/190509},
year = {1978},
date = {1978-04-01},
journal = { Astrophysical Journal Supplement Series},
volume = {36},
pages = {483-496},
abstract = {Cross sections for the important rotational transitions in molecular hydrogen collisions are presented for rotational levels to j = 11 and energies to 20,000 K. These have been obtained from extensive theoretical calculations. The resulting cross sections are fitted to a simple polynomial in the energy, and the coefficients are tabulated for easy utilization.},
keywords = {hydrogen, interstellar gas, molecular dynamics, Scattering},
pubstate = {published},
tppubtype = {article}
}

@article{Ramaswamy1977b,
title = {Low-temperature relaxation in gaseous H2 and D2},
author = {Ramakrishna Ramaswamy, Herschel Rabitz, Sheldon Green},
url = {https://doi.org/10.1063/1.434315},
doi = {10.1063/1.434315},
issn = {0021-9606},
year = {1977},
date = {1977-04-01},
journal = {The Journal of Chemical Physics},
volume = {66},
number = {7},
pages = {3021-3030},
abstract = {Various potentials have been used for generating scattering cross sections for rotational transitions in hydrogen isotope systems. Low‐temperature rates were calculated and the relaxation times compared with the results of sound absorption experiments. It is seen that the existing potentials could still be improved since they do not exactly reproduce the experimental results.},
keywords = {isotopes, Scattering},
pubstate = {published},
tppubtype = {article}
}