Structure of solid fluoroform

Abstract

The structure of fluoroform, CHF₃, was determined at 4·2, 40 and 70 K using neutron powder profile analysis. There is only one phase with a monoclinic space group P2₁/c. At the lowest temperature the lattice parameters are: a = 4·7561(1) Å, b = 6·6280(2) Å, c = 8·5232(2) Å β = 122·02(2)°. Starting positions and orientations of the four molecules in the unit cell were determined to high accuracy using an energy minimization process with atom-atom potentials. The structure is made up of weakly hydrogen bonded sheets with adjacent sheets related by centres of symmetry.

Additional information

Notes on contributors

O.S. Binbrek

On leave from King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia.