2002.Research interests cover a range of areas, with the characterisation of inorganic compounds using mass spectrometry being one of the central themes. Other research areas include the chemistry of the platinum group metals and gold, and applications of organophosphorus chemistry to the synthesis of novel ligands and the immobilisation of enzymes. He has published over 150 articles in refereed journals, together with three textbooks.Bill is married to Angela, a high school teacher, and they have two children, Laura and Liam. In his spare time, other interests include music, gardening and English mediaeval history.

Methods are described for characterising neutral metal carbonyl complexes using electrospray mass spectrometry, by converting them into ions with suitable reagents. Ionisation techniques included addition of OMe Ϫ generating [M ϩ OMe] Ϫ species, addition of Ag ϩ or Na ϩ ions giving the appropriate positive ion, abstraction of acidic hydrogen forming [M Ϫ H] Ϫ ions, or (in rare cases) oxidation giving radical cations [M] ϩ . The methods can be used on pure compounds or on mixtures. Fragmentation in the mass spectrometer can be minimised so that identification of parent species is unambiguous. Applications are demonstrated with a wide range of compounds including mononuclear and polynuclear binary carbonyls, and with derivatives containing phosphine, cyclopentadienyl, π-arene, σ-aryl and other ligands.Characterisation of metal carbonyl compounds, particularly the higher-nuclearity cluster compounds, has traditionally relied heavily on single-crystal X-ray crystallography. This is because microanalytical data are usually not particularly informative, 13 C NMR data are often limited by low sensitivity and fluxional processes, while structure assignment based on the interpretation of infrared spectra is limited to smaller molecules. The strong reliance on X-ray methods has a corollary; only compounds that form suitable single crystals become fully characterised. There is therefore a need for alternative means of investigating metal cluster compounds.Mass spectrometry has been applied to organometallic chemistry for many years, but the traditional electron impact method of ionisation is limited to thermally robust, neutral compounds of low molecular mass since appreciable vapour pressure is necessary at temperatures below the decomposition point. 1The development of FAB (fast-atom bombardment) methods extended the mass spectral technique to non-volatile compounds, but it is a rather violent means of ionisation so extensive fragmentation and recombination processes can make interpretation complicated.2 An alternative, developing technique based on laser desorption has been applied to organometallic systems, 3 but again aggregation processes complicate interpretation.In the past decade a new method of sample ionisation has been developed: electrospray mass spectrometry (ESMS).4 This involves spraying samples in solution from a charged outlet into an atmospheric-pressure source and then rapidly evaporating the solvent, leaving ions in the gas phase which are then transferred to a mass analyser. The process is gentle so that fragile samples can be examined, and fragmentation processes are minimised so that clean parent ions are usually found (although fragmentation can be induced by altering the conditions if further information is needed). It can also be applied directly to ionic species since solubility rather than volatility is the key factor. The new method has been extensively developed by those interested in biological systems since it enables mass spectrometry to be applied to high mass, fragile biomolecule...

Air-and moisture-sensitive compounds pose handling difficulties for chemists requiring mass spectrometric analysis. A simple pressurized sample infusion (PSI) system for electrospray ionization mass spectrometry using a Schlenk flask is presented, which allows straightforward one-off analyses as well as continuous reaction monitoring at any temperature up to the boiling point of the solvent.

Electrospray-ionization mass spectrometric studies of poly(methylaluminoxane) (MAO) in the presence of [Cp2 ZrMe2 ], [Cp2 ZrMe(Cl)], and [Cp2 ZrCl2 ] in fluorobenzene (PhF) solution are reported. The results demonstrate that alkylation and ionization are separate events that occur at competitive rates in a polar solvent. Furthermore, there are significant differences in ion-pair speciation that result from the use of metallocene dichloride complexes in comparison to alkylated precursors at otherwise identical Al/Zr ratios. Finally, the counter anions that form are dependent on the choice of precursor and Al/Zr ratio; halogenated aluminoxane anions [(MeAlO)x (Me3 Al)y-z (Me2 AlCl)z Me](-) (z=1, 2, 3…︁) are observed using metal chloride complexes and under some conditions may predominate over their non-halogenated precursors [(MeAlO)x (Me3 Al)y Me](-) . Specifically, this halogenation process appears selective for the anions that form in comparison to the neutral components of MAO. Only at very high Al/Zr ratios is the same "native" anion distribution observed when using [Cp2 ZrCl2 ] when compared with [Cp2 ZrMe2 ]. Together, the results suggest that the need for a large excess of MAO when using metallocene dichloride complexes is a reflection of competitive alkylation vs. ionization, the persistence of unreactive, homodinuclear ion pairs in the case of [Cp2 ZrCl2 ], as well as a change in ion pairing resulting from modification of the anions formed at lower Al/Zr ratios. Models for neutral precursors and anions are examined computationally.

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