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Determining conical intersection geometries is of key importance to understanding the photochemical reactivity of molecules. While many small- to medium-sized molecules can be treated accurately using multireference approaches, larger molecules require a less computationally demanding approach. In this work, minimum energy crossing point conical intersection geometries for a series of molecules have been studied using spin-flip TDDFT (SF-TDDFT), within the Tamm-Dancoff Approximation, both with and without explicit calculation of nonadiabatic coupling terms, and compared with both XMS-CASPT2 and CASSCF calculated geometries. The less computationally demanding algorithms, which do not require explicit calculation of the nonadiabatic coupling terms, generally fare well with the XMS-CASPT2 reference structures, while the relative energetics are only reasonably replicated with the MECP structure as calculated with the BHHLYP functional and full nonadiabatic coupling terms. We also demonstrate that, occasionally, CASSCF structures deviate quantitatively from the XMS-CASPT2 structures, showing the importance of including dynamical correlation.

There is high demand for new methods to modify peptides, for application in drug discovery and biomedicine. A C–H functionalization protocol for the olefination of tryptophan residues in peptides is described. The modification is successful for Trp residues at any position in the peptide, has broad scope in the styrene coupling partner, and offers opportunities for conjugating peptides with other biomolecules. For peptides containing both Trp and Phe, directing group manipulation enables full control of residue selectivity.

New methods for peptide modification are in high demand in drug discovery, chemical biology, and materials chemistry; methods that modify natural peptides are particularly attractive. A Pd-catalyzed, C–H functionalization protocol for the olefination of phenylalanine residues in peptides is reported, which is compatible with common amino acid protecting groups, and the scope of the styrene reaction partner is broad. Bidentate coordination of the peptide to the catalyst appears crucial for the success of the reaction.

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Tungstenvi oxo-salicylate complexes were prepared in moderate yield 47 to 63 by the reactions of WOCl4and two equivalents of either 3-methylsalicylic acid MesaliH2 or 3,5-di-isopropylsalicylic acid di-i-PrsaliH2. Performing the reaction in refluxing toluene afforded the two analogous ditungsten complexes 1, WOMesaliMesaliH2μ-O, and 2, WOdi-i-Prsalidi-i-PrsaliH2μ-O, however in refluxing hexane the mononuclear tungsten complex 3, WOdi-i-Prsalidi-i-PrsaliHCl, was isolated. The single crystal X-ray study of 1–3revealed a pseudo-octahedral geometry around the tungsten centres. Aerosol assisted chemical vapour deposition of 2or 3afforded brown tungsten trioxide thin films. These films were converted to yellow fully oxidised WO3on annealing in air at 550 °C for 30 minutes. The yellow WO3films demonstrate preferred orientation on the substrate and show interesting functional properties—photo induced hydrophilicity and photocatalytic activity.

Spinel ferrites of the form MFe2O4 (M = Mg, Co, Ni, Cu, Zn) and rhombohedral BaFe2O4 have been prepared by self-propagating high-temperature synthesis (SHS) reactions from iron, cobalt, iron(III) oxide and metal(II) oxides or peroxides. The driving force for the reactions is the oxidation of iron or cobalt powder. Reactions were carried out in air, under an oxygen atmosphere or with the addition of sodium perchlorate as an internal oxidising agent. Reactions were also carried out in the presence of an external magnetic field of 1.1 4;T. Pre-organisation of the reaction mixture in the applied field led to increases in the reaction velocity (from 2 to 5 4;mm 4;s–1) and temperature (950 to 1050 °C). The ratio of tetragonal to cubic phase observed for the CuFe2O4 product was increased by carrying out the reaction in the applied field. The inversion parameter observed for MgFe2O4 was also influenced by the applied field. All materials were characterised by X-ray powder diffraction (XRD), energy dispersive X-ray analysis (EDXA), scanning electron microscopy (SEM), FTIR, Mössbauer spectroscopy and vibrating sample magnetometry (VSM).

Aerosol assisted chemical vapour deposition of polyoxotungstate precursors n-Bu4N2W6O19 and n-Bu4N4H3PW11O39 produces films of WO3 − xand WO3on glass sunbstrates; the WO3films show significant photocatalytic decomposition of a test organic pollutant – stearic acid – when irradiated with either 254 or 365 nm radiation.