THE CRYSTAL-STRUCTURE OF TETRAETHYLAMMONIUM TETRAFLUOROBORATE, (C2H5)4NBF4

M(r) = 217.06, monoclinic, Cc, a = 12.471(8) angstrom, b = 7.381(6) an gstrom, c = 14.191(5) angstrom, beta = 115.58(5)degrees, V = 1178(1) a ngstrom3, Z = 4, D(m) = 1.232(5) g cm-3, D(x) = 1.224 g cm-3, lambda(M oK(alpha)) = 0.7107 angstrom, mu = 1.12 cm-1, F(000) = 464, R = 0.055 for 464 unique reflections with I > 3sigma(I). The interaction compoun d is formed by the tetraethylammonium cation and the tetrafluoroborate anion. The remarkable features of this crystal at 298 K are: i) the n on centrosymmetric structure; ii) the ordered distribution of the fluo roborate tetrahedra associated with the substituted ammonium ions, als o confirmed by NMR measurements, which is very different from the diso rdered configuration of the BF4 group in (CH3)4NBF4.