Internal Reorientations in K2ReH9via Widehyphen;Line and Pulsed Proton Resonance Studies

摘要

Proton spinndash;lattice relaxation timeslpar;T1rpar;and second momentslpar;M2rpar;have been measured as a function of temperature for K2ReH9. The activation energies for internal reorientation of ReH9equals;ions, and their rms errors, are 9.9thinsp;plusmn;thinsp;0.4 and 25.0thinsp;plusmn;thinsp;0.8 kJ/mole (2.4thinsp;plusmn;thinsp;0.1 and 6.0thinsp;plusmn;thinsp;0.2 kcal/mole), respectively, for typeaanddsites. Our results suggest that the barriers are determined by nearesthyphen;neighbor ReH9equals;sngbnd;ReH9equals;interactions.