Atomic Metal Ion Chemistry in the Gas Phase Diethard K. Bohme Ion Chemistry Laboratory Department of Chemistry Centre for Research in Mass Spectrometry Centre for Research in Earth & Space Science York University, Toronto, Canada Department of Chemistry Memorial University October 2, 2007 Ernest Rutherford: Ions are jolly little beggars, you can almost see them Create ions (in an ion source). Look at ions (with a mass spectrometer). resolve m/z, (dissociate), count Look at ions react (in a reaction cell). Chemical Mass Spectrometry Chemical Mass Spectrometry at York, since 2000 : 2000: Invention of ICP/DRC/MS (S. Tanner, V. Baranov, then at MDS/SCIEX) - Dynamic Reaction Cell (DRC) for the chemical resolution of isobaric interferences in elemental analysis - requires chemical data base for atomic-ion reactions. NSERC/NRC/MDS SCIEX/York Partnership. ICP/SIFT tandem mass spectrometer 2003: Suppression of chemical noise in MS, etc. (T. Covey, MDS SCIEX) NSERC/MDS SCIEX/York Partnership ESI/qQ/SIFT/QqQ multipole ms OUTLINE 1.ICP/SIFT tandem mass spectrometer (the universal atomic ion chemical mass spec) - Periodicities in Reactivities - The Special Case of Lanthanides - Atomic Cations as Catalysts - Influence of Ligation - Chemical Resolution of Atomic Isobars in ICP/DRC/MS: a Case Study 2.ESI/qQ/SIFT/QqQ multipole mass spectrometer (the ultimate chemical mass spectrometer) - Chemical Reactions of Atomic Metal Dications - Multiply-Charged Metallated Biological Ions 1. The Universal Atomic Ion Chemical Mass Spectrometer The ICP/SIFT/QqQ instrument __________________________________________________________________________________________________________ An Inductively-Coupled Plasma / Selected-Ion Flow Tube Mass Spectrometer Study of the Chemical Resolution of Isobaric Interferences. G.K. Koyanagi, V.I. Baranov, S. Tanner and D.K. Bohme, J. Anal. At. Spectr. 15, (2000). Argon Plasma 5500 K P = 1 atm Aqueous solution of the atomic salt is injected via a nebulizer into the Ar plasma Periodic Table of Atomic Salt Solutions Attractive Features of the ICP Ion Source intense: ca ions s -1 in first quad (Ar + with 0.1% metal ions), ca ions cm -3 in flow tube defined: thermal population of electronic states at ca K which relaxes toward 295 K. rapid: time to change metal ions ca. 30 s stable: not hours but weeks versatile: almost universal source of atomic ions Primary Oxidation and Nitration Nb + + N 2 O NbO + + N 2 NbN + + NO Further Oxidation NbO + + N 2 O NbO N 2 NbN + + N 2 O NbNO + + N 2 Clustering with N 2 O NbO N 2 O NbO 2 (N 2 O) + NbO 2 (N 2 O) + +N 2 O NbO 2 (N 2 O) 2 + NbO 2 (N 2 O) 2 + +N 2 O NbO 2 (N 2 O) 3 + NbNO + + N 2 O NbNO(N 2 O) + NbNO(N 2 O) + +N 2 O NbNO(N 2 O) 2 + NbNO(N 2 O) 2 + +N 2 O NbNO(N 2 O) 3 + Reactions of atomic cations: Nb + with N 2 O ________________________________________________________________ V.V. Lavrov et al., J. Phys. Chem. A 106 (2002) 4581. 59 atomic cations 15 different molecules O 2, NO, N 2 O, NO 2, CO 2, CS 2, OCS, D 2 O, NH 3, CH 4, CH 3 F, CH 3 Cl, SF 6, C 6 H 6, C 6 F 6 Some MO + oxide ions Surfing the Periodic Table 61 atomic cations x 15 molecules = 915 reactions !!Web Data Base Periodicities in Reactivities n up to 4 ! k/k c OA (M + ) /kcal mol -1 TS >6.4 x x x D Fe + 1 S Y + H 0 /(kcal mol -1 ) + + B3LYP/sdd/6-311+G* 3 F Rh + Kinetic barrier due to electron interaction during bond redisposition (conventional activation barrier). Slow and spin forbidden a for formation of ground state MO +. k r H o (cm 3 s -1 ) (kcal mol -1 ) Cr + (X 6 S) + N 2 O CrO + ( 4 - ) + N 2