A Theoretical Investigation of the Nonrigid Six-Coordinate Compounds [Mo(R)F_5],[W(R)F_5],and Related Compounds

摘要

Density functional calculations for [M(CH_3)F_5],[M(CF_3)F_5],[M-(CH_3S)F_5],and [M(CF_3S)F_5] (M = Mo,W) show that they are expected to be non-rigid molecules,with energy barriers for the octahedral-trigonal-prismatic interchange as low as 7.2 kJ mol~(-1).The ground state for the CH_3- and CF_3- compounds is trigonal prismatic,for the CH_3S- and CF_3S- compounds,(distorted) octahedral.All calculated compounds [M(C_6F_5)_nF_(6_n)] (M = Mo,W) have a trigonal-prismatic ground state,whereas the situation for [M(C_6H_5)_nF_(6-n)] (M = Mo,W) is more complex.