TY - JOUR
T1 - Quantum dynamical calculation of all rovibrational states of HO2 for total angular momentum J = 0-10
AU - Chen, Wenwu
AU - Poirier, Bill
N1 - Funding Information:
This work was largely supported by the Office of Advanced Scientific Computing Research, Mathematical, Information, and Computational Sciences Division of the US Department of Energy under contract DE-FG03-02ER25534. Additional support from The Welch Foundation (D-1523) is also acknowledged. The authors wish to express special gratitude to Michael Minkoff and Albert F. Wagner, whose interest and motivation have made the parallel aspects of this work possible. Other researchers, notably Tucker Carrington, Jr., Stephen K. Gray, Dinesh K. Kaushik, Richard Lehoucq, Dmitry M. Medvedev, Mark Sears, Ron Shepard, and Barry F. Smith, are also acknowledged for many stimulating discussions. In addition, we gratefully acknowledge the Jazz Linux Cluster Group of the Mathematics and Computer Science Division at Argonne National Laboratory, for technical support, and for use of the Jazz facility, as well as the Texas Tech University High Performance Computing Center, for their assistance, and use of the Hrothgar facility.
PY - 2010/4
Y1 - 2010/4
N2 - The energy levels and wavefunctions for all rovibrational bound states of HO2 are systematically computed, for all total angular momentum values J = 0-10. The calculations are performed using ScalIT, a suite of software modules designed to enable quantum dynamics and related calculations to be performed on massively parallel computing architectures. This is the first-ever application of ScalIT to a real (and very challenging) molecular application. The codes, and in particular, the algorithms (optimal separable basis, preconditioned inexact spectral transform, phase space optimized discrete variable representation basis) are so efficient that in fact, the entire calculation can be performed on a single CPU-although parallel scalability over a small number of CPUs is also evaluated, and found to be essentially perfect in this regime. For the lowest 11 vibrational states, the rotational levels for J = 0-10 fit fairly well to a rigid rotor model, with all vibrational-state- dependent rotational constants, Beff(v), close to values obtained from a previous calculation for J = 0 and 1 [J Chem Phys 107:2705, 1997]. However, comparatively larger discrepancies with the rigid-rotor model are found at the higher J values, manifesting in the observed K-splitting (along the O-O bond) of rovibrational levels. This supports earlier work [J Chem Phys 113:11055, 2000] suggesting that Coriolis coupling is quite important for this system.
AB - The energy levels and wavefunctions for all rovibrational bound states of HO2 are systematically computed, for all total angular momentum values J = 0-10. The calculations are performed using ScalIT, a suite of software modules designed to enable quantum dynamics and related calculations to be performed on massively parallel computing architectures. This is the first-ever application of ScalIT to a real (and very challenging) molecular application. The codes, and in particular, the algorithms (optimal separable basis, preconditioned inexact spectral transform, phase space optimized discrete variable representation basis) are so efficient that in fact, the entire calculation can be performed on a single CPU-although parallel scalability over a small number of CPUs is also evaluated, and found to be essentially perfect in this regime. For the lowest 11 vibrational states, the rotational levels for J = 0-10 fit fairly well to a rigid rotor model, with all vibrational-state- dependent rotational constants, Beff(v), close to values obtained from a previous calculation for J = 0 and 1 [J Chem Phys 107:2705, 1997]. However, comparatively larger discrepancies with the rigid-rotor model are found at the higher J values, manifesting in the observed K-splitting (along the O-O bond) of rovibrational levels. This supports earlier work [J Chem Phys 113:11055, 2000] suggesting that Coriolis coupling is quite important for this system.
KW - Quantum dynamics
KW - parallel computing
KW - rovibrational spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=77954182341&partnerID=8YFLogxK
U2 - 10.1142/S0219633610005815
DO - 10.1142/S0219633610005815
M3 - Article
AN - SCOPUS:77954182341
VL - 9
SP - 435
EP - 469
JO - Journal of Theoretical and Computational Chemistry
JF - Journal of Theoretical and Computational Chemistry
SN - 0219-6336
IS - 2
ER -