Crawford, EDyson, PJForest, OKwok, SMcIndoe, JS2006-05-302006-05-30200610.1007/s10876-005-0043-8https://infoscience.epfl.ch/handle/20.500.14299/230257WOS:0002371905000058533The electrospray ionisation mass spectra (EDESI-MS) of Ru<sub>6</sub>C(CO)<sub>16</sub>(PPh<sub>3</sub>) and Ir<sub>4</sub>(CO)<sub>11</sub>(PR<sub>3</sub>) (PR<sub>3</sub> = PPh<sub>3</sub>, P(p-C<sub>6</sub>H<sub>4</sub>OMe)<sub>3</sub>, P(p-C<sub>6</sub>H<sub>4</sub>NMe<sub>2</sub>)<sub>3</sub>, P(p-C<sub>6</sub>H<sub>4</sub>Cl)<sub>3</sub>, P(OPh)<sub>3</sub>, P(OMe)<sub>3</sub>, PO<sub>3</sub>C<sub>5</sub>H<sub>9</sub>) are described and the relative importance of carbonyl loss vs. phosphine loss as a fragmentation pathway is assessed. Qual., the phosphine ligands bind more strongly to Ir<sub>4</sub>(CO)<sub>11</sub> clusters than to Ru<sub>6</sub>C(CO)<sub>16</sub>. The influence on the collision cell pressure on MS/MS spectra of transition metal carbonyl cluster anions is also explored showing that a greater, simultaneous, distribution of fragment ions is produced as the collision cell pressure is increased.Energy-dependent Electrospray Ionisation Mass Spectrometry of Carbonyl Clusterstext::journal::journal article::research article