NQR AND X-RAY STUDY OF BIS(4-METHYLPYRIDINIUM) PENTABROMOANTIMONATE(III), (4-CH3C5H4NH)2SBBR5

The crystal structure of the title compound was determined (T=300 K): C-i(1)-P1BAR, Z=2, a=1085.8, b=1064.3, c=929.0 pm, alpha=97.83, beta=108.86, gamma=99.24-degrees, R(F)=0.047, R(w)(F)=0.041. Characteristic for the structure is the dimer structure of SbBr52- ion. The atomic coordination around the Sb atom is a distorted octahedron. The Br-81 NQR spectrum was studied in the temperature range 77 less-than-or-equal-to T/K less-than-or-equal-to 350. The Br-81 NQR frequencies are spread out over a wide range at 77 K: 37 less-than-or-equal-to nu(Br-81)/MHz less-than-or-equal-to 111. The temperature dependence of the NQR frequencies and of their spread is given as is an assignment of Br-81 NQR lines to the positions of Br atoms in the anion.