Atomic Metal Ion Chemistry in the Gas Phase

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 Chemical Mass Spectrometry  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) Ernest Rutherford: “Ions are jolly little beggars, you can almost see them“ 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 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 ESI/qQ/SIFT/QqQ multipole mass spectrometer (the ultimate chemical mass spectrometer) - Chemical Reactions of Atomic Metal Dications - Multiply-Charged Metallated Biological Ions The Universal Atomic Ion Chemical Mass Spectrometer The ICP/SIFT/QqQ instrument Argon Plasma P la s m a S o u rc e T u rb o Pum p H e liu m I n le t R eagent I n le t B lo w e r T r ip le Q u a d r u p o le 5500 K P = atm D iffu s io n Pum p T u rb o Pum p T u rb o Pum p Aqueous solution of the atomic salt is injected via a nebulizer into the Ar plasma 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, 1207-1210 (2000) Periodic Table of Atomic Salt Solutions Attractive Features of the ICP Ion Source  intense: ca.1011 ions s-1 in first quad (Ar+ with 0.1% metal ions), ca 107 ions cm-3 in flow tube  defined: thermal population of electronic states at ca 5500 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 Reactions of atomic cations: Nb+ with N2O 103 Nb + NbO 2+ + NbO ·(N 2O)2 NbNO +·(N 2O)2 102 Ion Signal NbO 2+·(N 2O)3 NbO 2+·N 2O NbNO + NbO + 101 Nb+ + N2O  NbO+ + N2  NbN+ + NO Further Oxidation NbO+ + N2O  NbO2+ + N2 NbN+ + N2O  NbNO+ + N2 Clustering with N2O NbO2+ + N2O  NbO2(N2O)+ NbO2(N2O)+ +N2O NbO2(N2O)2+ NbO2(N2O)2+ +N2O NbO2(N2O)3+ + NbNO ·N 2O NbNO +·(N 2O)3 NbN + 100 Primary Oxidation and Nitration + + NbNO + N O  NbNO(N O) 2 N 2O flow/(10 17 molecules s -1) NbNO(N2O)+ +N2ONbNO(N2O)2+ NbNO(N2O)2+ +N2ONbNO(N2O)3+ V.V Lavrov et al., J Phys Chem A 106 (2002) 4581 0.0 1.0 2.0 3.0 4.0 Surfing the Periodic Table H He 59 atomic cations Li Be Na M g K C Al Si Ca Sc Rb Sr B Y Ti V O F Ne P S Cl Ar Cr M n Fe Co Ni Cu Zn Ga Ge As Se Br Kr Z r N b M o T c R u R h P d A g C d In S n S b T e C s B a L a H f Ta Fr Ra Ac N W Re Os Ir I Xe Pt Au Hg Tl Pb Bi Po At Rn C e Pr N d Pm Sm Eu G d Tb D y H o Er Tm Yb Lu Some MO+ oxide ions 15 different molecules O2, NO, N2O, NO2, CO2, CS2, OCS, D2O, NH3, CH4, CH3F, CH3Cl, SF6, C6H6, C6F6 1000 5000 2500 Discontinuities in reactivity provide an opportunity for chemical resolution M+ + SF6  MFn+ + SF6-n  M+(SF6 )  SFn+ + MF6-n C Ping and D.K Bohme, J Phys.Chem A, in preparation The Ultimate Chemical Mass Spectrometer The ESI/qQ/SIFT/QqQ instrument A – skimmer, B – q0 reaction cell, C extended stubbies, D – extended q0 rod set _ A novel chemical reactor suited for studies of biophysical chemistry: construction and evaluation of a selected ion flow tube utilizing an electrospray ion source and a triple quadrupole detection system G.K Koyanagi et al Int J Mass Spectrom 265, 295-301 (2007) Chemical Reactions of Atomic Metal Dications Ozonolysis of Metal Dications Oxidation of Ca++ is Initiated by Charge Separation Ca++ + O3  CaO+ + O2+ (k = 1.5 × 10-9 cm3 s-1)   CaO+ + O3  CaO2+ + O2   (k = × 10-10 cm3 s-1) CaO2+ + O3  CaO3+ + O2 (k = × 10-10 cm3 s-1) 100 M CaAcetate in H2O/CH3OH (1/1) Ba++  BaO3++  BaO6++  BaO9++  BaO12++ k01 = 1.1 × 10-11 cm3 s-1 k02 = 2.9 × 10-10 cm3 s-1 k13 = 1.2 × 10-10 cm3 s-1 k4 = 1.8 × 10-10 cm3 s-1 Ba++ H2O O3 Ba(H2O)++ BaO3++ H2 O O3 BaO O3 BaO9++ 10 M BaCl2 in H2O/CH3OH (1/1) O3 BaO12++ ++ Ba(H2O)O3++ H2 O H2 O Ba(H2O)2++ Ba(H2O)O6++ 10 Ca 2+ -1 Ion Signal/(s ) D3O 10 2+ + + Ca 2+ Ca(D2O) CaOD + CaOD(D2O) 2+ Ca(D2O) 10 CaOD(D2O) + CaOD(D2O)5 10 + + CaOD(D2O)2 + D2O hydrolysis of + CaOD + D3O CaOD(D2O)3 CaOD(D O) + + CaOD(D2O)3 + CaOD(D2O)2 + CaOD(D2O)4 Ca2+ + 10 CaOD(D2O)5 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 18 -1 -1 Ion Signal/(s ) D2O flow/(10 molecules s ) 10 10 10 Ba 2+ 2+ 2+ 10 10 10 10 10 BaD2O 2+ Ba(D2O)5 2+ Ba(D2O)6 Ba 2+ Ba(D2O) 2+ Ba(D2O)2 2+ 2+ Ba(D2O)2 Ba(D2O)4 2+ 2+ Ba(D2O)4 Ba(D2O)7 2+ Ba(D2O)3 2+ Ba(D2O)3 2+ Ba(D2O)5 2+ Ba(D2O)6 2+ Ba(D2O)7 0.0 0.5 1.0 18 Ba2+ 1.5 -1 D2O flow/(10 molecules s ) in He at 0.35 Torr and 295 K D2O Hydrolysis of Metal Dications M+ RE/eV Products k/ cm s-1 Higher-order Products - Mg2+ 15.0 Mg+ + D2O+ Ca2+ 11.9 Ca2+D2O 1.4x10-9 MgOD+, D3O+ 2.3x10-11 Ca2+D2O CaOD+ + D3O+ 7.9x10-10 CaOD+(D2O)1-5 Sr2+ 11.0 Sr2+D2O < 1x10-12 Sr2+(D2O)2-8 Ba2+ 10.0 Ba2+D2O 6.7x10-12 Ba2+(D2O)2-7 Multiply-Charged Metallated Biological Ions DNA is intrinsically very stable (thanks to Mother Nature)! k295 / cm3 molecule-1 s-1 NH2 N HO CH2 N H H H O P - N O H O N O H N OCH2 H H P O H O O NH2 N H H OCH2 O O O N H NH2 H H N O P - OCH2 O N2O