Photoelectron spectroscopy of AgCl, AgBr, and AgI vapors

Abstract

He I photoelectron spectra of AgCl, AgBr and AgI vapors have been obtained which differ significantly from earlier work. In each instance, the characteristic features of the diatomic molecule are prominent. The spectral features separate into a valence region, predominantly halogen p-like, and a deeper region, predominantly of Ag 4d character. The latter is split by spin–orbit and ligand field interactions, which are parametrized from the experimental data. Relativistic calculations of the Xα–DVM–SCC type have been performed for these species. At the transition state level, they agree very well with the experimental peak positions. Nonrelativistic calculations of this type have been performed for CuCl and cyclic Cu3Cl3. Unlike the AgX species, the CuCl and Cu3Cl3 exhibit strong mixing of metal d and halogen p orbitals for the uppermost occupied orbital, and other Cu 3d-like orbitals above the Cl 3p-like orbitals. It is suggested that the occurrence of Cu 3d orbitals in the valence region may play a role in the anomalous diagmagnetic signal and large conductivity changes of CuCl condensed from the vapor.

Evidence for trimers evaporation in silver bromide clusters

“…The vapor of cuprous halides CuCl, CuBr, CuI contains mainly trimers but also tetramers [1][2][3][4], whereas monomers and dimers are roughly equally abundant in the vapors of AgCl, AgBr and AgI [5]. It has also been demonstrated that the trimer is a building block in silver hydroxide clusters [6][7][8].…”

“…The trimer is known to play a special role in noble metal halides in the gas phase: an amazing common property of all these compounds is the unusual abundance of trimers in their vapor [1][2][3][4][5]. The vapor of cuprous halides CuCl, CuBr, CuI contains mainly trimers but also tetramers [1][2][3][4], whereas monomers and dimers are roughly equally abundant in the vapors of AgCl, AgBr and AgI [5].…”

Ab Initio Study of Neutral and Charged Copper Bromide (CuBr) n (+) Clusters (n = 1–6)

“…The nature of bondings (covalent or ionic) is still controversial. In gas phase, an amazing common property of all these compounds is the unusual abundance of trimers in their vapor [4][5][6][7][8][9][10][11][12], although smaller molecules like monomers, and eventually dimers are expected for metal halides. The relative large stability of the trimer was also shown in experiments of fragmentation of metastable clusters in the case of silver bromide [13,14].…”

Structure and stability of coinage metal fluoride and chloride clusters (MnFn and MnCln, M = Cu, Ag, or Au; n = 1–6)

“…The nature of bondings (covalent or ionic) is still controversial. In gas phase, an amazing common property of all these compounds is the unusual abundance of trimers in their vapor,[4–12] and even tetramer in the case of CuCl vapor,[13] although smaller molecules such as monomers, and eventually dimers are expected for metal halides. Very early, Schomaker and coworkers proposed a six‐membered alternating ring model to describe the structure of the cuprous chlorides trimer Cu 3 Cl 3 .…”