Ps. Weiser et al., Infrared spectra of Cl--(C2H2)(n) (1 <= n <= 9) anion clusters: Spectroscopic evidence for solvent shell closure, J CHEM PHYS, 110(19), 1999, pp. 9443-9449
Mid-infrared vibrational predissociation spectra of mass selected Cl--(C2H2
)(n) (1 less than or equal to n less than or equal to 9) complexes have bee
n recorded in the vicinity of the acetylene nu(3) vibrational band (2700-34
00 cm(-1)). For clusters containing up to 6 acetylene ligands, the spectra
each feature a single dominant band, shifted to lower frequency from the nu
(3) C-H stretch band of free acetylene, and are consistent with interior so
lvation structures, whereby roughly equivalent acetylene molecules are boun
d end-on to a central chloride anion. Spectra of the n=7, 8, and 9 complexe
s, display multiple peaks and provide evidence for acetylene molecules situ
ated in a second solvation shell and also for the existence of multiple iso
meric forms. Depending on the cluster size, the inner solvation shell conta
ins 6-8 acetylene molecules. (C) 1999 American Institute of Physics. [S0021
-9606(99)01818-8].