Crystal structure of 4 and its use as a chemical vapor deposition precursor for silver films

Article abstract of DOI:10.1016/0022-328X(93)80124-T

Silver films have been prepared by the metal-organic chemical vapor deposition of perfluoro-1-methyl-1-propenylsilver tetramer, 4, at 275 deg C and 10^-4 Torr; the silver films contain only traces ( less than 1percent) of fluorine and oxygen and no carbon.The principal organic byproducts formed during deposition are trans-CF3CF=CH(CF3) (50percent) and CF3C<*>CCF3 (40percent).It is argued that silver metal is produced by elimination of CF3C<*>CCF3 from trans-4 to form silver(1) fluoride, which defluorinates to form silver metal.The crystal structure of trans-4 was determined and reveals that this compound is a tetramer that consists of a square plane of silver atoms in which each edge is bridged by a trans-perfluoro-1-methyl-1-propenyl ligand.The average distances and angles are: Ag-Ag = 2.761 Angstroem, Ag-C = 2.19 Angstroem, Ag-C-Ag = 78.3 deg and C-Ag-C = 166.7 deg.Crystal data: monoclinic, space group P2₁/c, a = 9.480(5) Angstroem, b = 15.589(6) Angstroem, c = 18.919(4) Angstroem, β = 90.27(3) deg, V = 2796(4) Angstroem³, Z = 4, R_F = 0.070, and R_wF = 0.089 on 433 variables and 3617 data with I above 2.58 ?(I).