A COOPERATIVE MECHANISM AS THE MAIN SOURCE OF THE MARKED STRUCTURAL DIFFERENCES BETWEEN SOLID AND GASEOUS HCN CENTER-DOT-CENTER-DOT-CENTER-DOT-BF3

The marked structural differences between the solid- and gas-phase str uctures of HCN ... BF3 are reproduced by ab initio calculations employ ing the D95 * and 6-31 + + G * * basis sets. Specifically, the short ening in the B ... N distance and the distortion in the N ... B-F angl e are reproduced to within 0.1 Angstrom and 4 degrees, respectively. T he results suggest that a cooperative mechanism, where the nearest nei ghbour is deeply involved is responsible for the structural difference s between the two states of HCN ... BF3. (C) 1998 Published by Elsevie r Science B.V. All rights reserved.