STRUCTURE AND STABILITY OF BF3-ASTERISK-F AND ALF3-ASTERISK-F SUPERHALOGENS

Structure and stability of BF4, AlF4, BF4- and AlF4- are studied at th e MBPT(4) and CCSD(T) levels of theory. AlF4 is confirmed to have a co nfiguration of an adduct type, which is stable by 5.8 kcal/mol towards AlF3 + F. BF4 has to be considered rather as a Van der Waals complex which is bound by 1.6 kcal/mol. BF3 F and AlF3 * F possess very high adiabatic electron affinities of 6.75 and 7.93 eV, respectively, and are superhalogens. We computed the adiabatic electron affinities of BF , and AlF3 to be -0.76 and 0.90 eV, respectively, which indicates that BF3- is metastable. (C) 1998 Elsevier Science B.V. All rights reserve d.