Molecular Structure of Bromoform as Determined by a Joint Analysis of Electron Diffraction and Microwave Data

The gas phase molecular structure of bromoform has been studied by electron diffraction. By a joint analysis of the diffraction results and the moments of inertia for CH79Br3, CD79Br3, CH81Br3, and CD81Br3 obtained by Williams et al., the bond distances in rg and the bond angles in have been determined as follows: rg(C–Br)=1.924±0.005 Å, rg(Br…Br)=3.175±0.003 Å, rg(C–H)=1.111±0.046 Å, (BrCBr)=111.7±0.4°, and (HCBr)=107.2±0.5°. The uncertainties represent the estimated limits of error. The anharmonicity parameter of the Morse-type potential, a3, for the nonbonded Br…Br atom pair has been estimated as −1.3±0.9 Å−1.