Shared Memory Parallelization of the Multiconfiguration Time-Dependent Hartree Method and Application to the Dynamics and Spectroscopy of the Protonated Water Dimer

Abstract

The Heidelberg multiconfiguration time-dependent Hartree (MCTDH) code for propagation of wavepackets is parallelized using shared memory techniques. A parallelization scheme based on a scheduler–worker approach is introduced. The performance of the parallel code is evaluated by benchmark tests. Using the parallelized version of the MCTDH code, the infrared absorption spectrum of the protonated water dimer ${\rm{H}}:5 {\rm{O}}_2^+$ is simulated in full dimensionality (15D) in the spectral range 0–4,000 cm-1. The middle spectral region, between 800 and 2,000 wavenumbers, is discussed and the couplings that shape this region of the spectrum are identified and explained, and the corresponding spectral lines are assigned.