Computer Physics Communications
We present SpectrumSDT – a program for calculations of energies and lifetimes of bound rotational-vibrational states below and scattering resonances above the dissociation threshold on a global potential energy surface of a triatomic system, which may include stable molecules, weekly-bound van-der-Waals complexes, and unbound atom + diatom scattering systems. Large-amplitude vibrational motion is treated explicitly using hyper-spherical coordinates. Three options for the rotational-vibrational interaction are supported: uncoupled (symmetric top rotor), partially coupled (to include interaction between several nearest states only) and full-coupled (vibrating asymmetric-top rotor). In addition to energies and lifetimes, SpectrumSDT is able to integrate ro-vibrational wave functions over the user-defined regions of potential energy surface, which helps to classify these states. In this release of the code, SpectrumSDT is limited to ABA-type molecules with wave functions that do not extend into the regions near Eckart singularities.
Gayday, Igor; Teplukhin, Alexander; Moussa, Jonathan; and Babikov, Dmitri, "SpectrumSDT: A Program for Parallel Calculation of Coupled Rotational-Vibrational Energies and Lifetimes of Bound States and Scattering Resonances in Triatomic Systems" (2021). Chemistry Faculty Research and Publications. 1059.
Available for download on Monday, October 02, 2023