Ion cyclotron resonance spectroscopy, and

The molecule BH must be sufficiently stable that its bond energy (enthalpy of atomization. AWa-m) and ionization potential (IEUH) can be measured. Once several proton affinities have been established in this way. many mote may be obtained by a technique known as ion cyclotron resonance spectroscopy and related methods,20 which measure the equilibrium concentrations of the species involved in the competition ... 

D. M. Fedor, R. B. Cody, D. J. Burinsky, B. S. Freiser, and R. G. Cooks, "Dissociative Excitation of Gas-Phase Ions. A. Comparison of Techniques Utilizing Ion Cyclotron Resonance Spectroscopy and Angle-Resolved Mass Spectrometry," Int. J. Mass Spectrom. Ion Proc., 39., 55-64 (1981). 

This volume contains excellent discussions of the various methods for studying ion-molecule reactions in the gas phase, including high pressure mass spectrometry, ion cyclotron resonance spectroscopy (and FT-ICR) and selected ion flow tube mass spectrometry. 

The gas-phase reaction of diborane(6) with a series of anions has been investigated. Experimental data were obtained using ion cyclotron resonance spectroscopy, and ab initio calculations at the 4-31G+ basis set level were used to ascertain the importance of thermodynamic factors in the reactions. Two distinct reaction channels, shown in Fig. 2-45, were observed, and they are perceived to proceed via the same intermediate [B2H6X]" complex, from which the dissociation products arise [9]. 

ICP/MS. inductively coupled plasma and mass spectrometry used as a combined technique ICR. ion cyclotron resonance (spectroscopy)... 

Asamoto, B. and Dunbar, R.C., Analytical Applications of Fourier Transform Ion Cyclotron Resonance Spectroscopy, VCH, New York, 1991. 

Lehman, T.A. and Bursey, M.M., Ion Cyclotron Resonance Spectroscopy, Wiley, New York, 1976. 

The apparatus and techniques of ion cyclotron resonance spectroscopy have been described in detail elsewhere. Ions are formed, either by electron impact from a volatile precursor, or by laser evaporation and ionization of a solid metal target (14), and allowed to interact with neutral reactants. Freiser and co-workers have refined this experimental methodology with the use of elegant collision induced dissociation experiments for reactant preparation and the selective introduction of neutral reactants using pulsed gas valves (15). Irradiation of the ions with either lasers or conventional light sources during selected portions of the trapped ion cycle makes it possible to study ion photochemical processes... 

M. B. Comisarow and A. G. Marshall. Fourier Transform Ion Cyclotron Resonance Spectroscopy. Chem. Phys. Lett., 25(1974) 282- 283. 

The use of ion cyclotron resonance spectroscopy to measure the proton affinity of a molecule in the gas phase is now well established (for example, Ref.91 ). The application of the technique to transition metal organometallic compounds is a more recent development and some results are shown in Table 22. In all molecules studied so far it is generally observed that the dissociation energy of a cationic... 

Hehre and co-workers (DeFrees et al., 1977, 1979a) have published both experimental and theoretical evidence in support of negative ion (anionic) hyperconjugation. These workers determined the free energies for the gas-phase hydron3 transfer equilibria (31), (32) and (33) by pulsed ion cyclotron resonance spectroscopy (Wolf et al., 1976). These equilibria, which involve the gas-phase formation of a methylamino, a methoxy and a thiomethoxy anion, all lie to the right, i.e. the formation of the isotopically light anion is favoured. These results were rationalized in terms of the MO... 

Silene 2, 1-fluorosilene 602 and 1,1-difluorosilene 603 have been examined by FT ion cyclotron resonance spectroscopy in order to estimate the jr-bond strength. Bracketing studies with various bases (B) and fluoride acceptors (A) gave values for the proton and fluoride affinity of the silenes284. The TT-bond energy was calculated by thermochemical cycles and found to increase with fluorine substitution. The data are given in Table 16. 

The intrinsic basicity (i.e. the standard Gibbs energy change for reaction 158 in the gas phase) for a variety of compounds XC(=S)Y have been determined by means of Fourier Transform Ion Cyclotron Resonance Spectroscopy (FT ICR) by the groups of Abboud39 and of Gal520. 

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