Preparation of the binary technetium bromides: TcBr3 and TcBr4.
TcBr(3) (1) and TcBr(4) (2) were synthesized by reaction of Tc metal with elemental bromine at 400 degrees C. Single crystal XRD measurements indicate that TcBr(3) crystallizes in the orthorhombic space group Pmmn (a = 11.0656(2) A, b = 5.9717(1) A, c = 6.3870(1) A). The structure consists of infinite chains of face-sharing TcBr(6) octahedra with a regular alternation of short and long Tc-Tc distances (2.8283(4) A, 3.1434(4) A). TcBr(4) crystallizes in the orthorhombic space group Pbca (a = 6.3237(5) A, b = 12.1777(9) A, c = 14.7397(11) A). TcBr(4) contains infinite chains of edge-sharing TcBr(6) octahedra with no apparent metal-metal bond (Tc-Tc = 3.7914(4) A). Technetium tribromide is isomorphous with RuBr(3) and MoBr(3), while TcBr(4) is isomorphous with PtBr(4) and OsBr(4).
Poineau
Frederic
F
Department of Chemistry, University of Nevada-Las Vegas, Las Vegas, Nevada 89154, USA. freder29@unlv.nevada.edu
Rodriguez
Efrain E
EE
Forster
Paul M
PM
Sattelberger
Alfred P
AP
Cheetham
Anthony K
AK
Czerwinski
Kenneth R
KR