Vibrational relaxation and energy transfer in the hydrogen system at temperatures between 110 and 300K

Rovibrational energy transfer in collisions of H2with D2: a full-dimensional wave packet propagation study

“…Our computed rotationally-averaged rate coefficient shows acceptable agreement with the measured data for room temperature and above, where most of the data was taken. But for lower temperatures, the temperature dependence of our rate coefficient becomes weaker than suggested by experiment, leading to significant discrepancies with the low temperature data from [44].…”

“…Later measurements [42][43][44] confirmed their results and provided more data for temperatures as low as T ¼ 150 K. Starting to reproduce these results with MCTDH is one of the purposes of this study. In the present work, a variant of the BMKP PES was used and the Heidelberg MCTDH package [45] was employed to propagate wave packets and to analyse their quantum flux as in our previous works.…”

“…Rotationally averaged rate coefficient for vibrational energy transfer from H 2 to D 2 , comparing our result (solid line) with experimental data from Bott [40], Pirkle and Cool [41], Segatz et al [43], and Schneider-Ku¨hle et al [44]. The dashed line shows our result for a system of pure para-H 2 /ortho-D 2 .…”

“…The rate of vibrational transfer between H 2 and D 2 molecules has been the subject of several experimental studies [40][41][42][43][44]. When comparing our results to the measured data, it is important to note that pure rotational transitions occur much (100-1000 times) faster than transitions involving changes of the vibrational states [42,72].…”

“…Third, although several different measurements of k vv (T) have been done and agree rather well with each other, only one of these measurements [44] provides Figure 9. Rotationally averaged rate coefficient for vibrational energy transfer from H 2 to D 2 , comparing our result (solid line) with experimental data from Bott [40], Pirkle and Cool [41], Segatz et al [43], and Schneider-Ku¨hle et al [44].…”