Atom—Molecule Kinetics Using ESR Detection. II. Results for D+H2→HD+H and H+D2→HD+D

摘要: The wide temperature range, fast flow kinetic system with ESR atom detection described recently has been used to measure rate constants for the isotopic reactions D+H2→HD+H, H+D2→HD+D, over range 250°—750°K and 300°—750°K, respectively. precision of data at a given is about ±5%, except lowest in each case where it ±8%. It believed that this also represents accuracy. In 450°—750°K both sets are Arrhenius linear obey (cubic centimeters mole−1·second−1) k1=4.4×1013exp(−7610/RT);  k2=4.9×1013exp(−9390/RT). Interpretation portion made terms absolute theory no tunneling. A potential‐energy surface constructed by fitting experimental activation energies Sato method as Weston essential agreement latter's results H3 complex. properties complex give pre‐exponential factors satisfactory experiment. ratio k1/k2 region closely predicted simply limiting form using collision frequencies zero‐point energy difference between H2 D2. shown nonlinear below 450°K apparent ``tunnel corrections'' τ two which qualitatively τ1 τ2.