Pressure Tuning of the Electronic Spectra of Quasi-One-Dimensional Mixed Valence Semiconductors

The effects of high pressure on the electronic spectra of the mixed valence semiconductors, K$\sb4$(Pt$\sb2$(P$\sb2$O$\sb5$H$\sb2)\sb4$X) $\cdot$3H$\sb2$O; X = Cl, Br were investigated to 10.0 GPa. Their electronic spectra consist of transitions seen in the reduced salt, K$\sb4$(Pt$\sb2$(P$\sb2$O$\sb5$H$\sb2)\sb4$) $\cdot$2H$\sb2$O, and the oxidized salt, K$\sb4$(Pt$\sb2$(P$\sb2$O$\sb5$H$\sb2)\sb4$Cl$\sb2$) $\cdot$2H$\sb2$O, modified to some extent, along with an intervalence charge transfer (IVCT) band characteristic of the mixed valence complex itself. The reduced salt and the oxidized salt have also been studied so that direct comparison with the monohalide could be made. For all four complexes, two first order effects controlled the pressure-induced shifts on the energy of the electronic transitions. These effects, which are discussed in terms of simplified molecular orbital diagrams, are pressure-induced changes in the ligand field splitting in the molecule and an increase in the splitting between the bonding and anti-bonding orbitals within a manifold.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Stroud, Mary Ann

Contributors dc:contributor

• Drickamer, Harry G.,

• Chemistry, Inorganic
• Engineering, Materials Science

Identifier

(UMI)AAI8823261

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/69793