Mark A. Smith

Name: Smith, Mark

Organization: University of Arizona , USA

Department: Department of Chemistry

Title: Emeritus(PhD)

Chemicals
References

Variable-Temperature Rate Coefficients for the Electron Transfer Reaction N2+ + H2O Measured with a Coaxial Molecular Beam Radio Frequency Ring Electrode Ion Trap

Co-reporter:Bing Yuan, Zachary Scott, George Tikhonov, Dieter Gerlich, and Mark A. Smith

The Journal of Physical Chemistry A 2011 Volume 115(Issue 1) pp:25-29

Publication Date(Web):December 13, 2010

DOI:10.1021/jp105850b

The neutral molecule temperature dependence of the rate coefficient for the electron transfer reaction from H2O to N2+ is determined using a coaxial molecular beam radio frequency ring electrode ion trap (CoMB-RET) method. The temperature of the N2+ ions was maintained at 100 K, while the effusive water beam temperature was varied from 300 to 450 K. The result demonstrates the neutral molecule rotational/translational energy dependence on the rate coefficient of an ion−dipolar molecule reaction. It is found that the rate coefficient in the above temperature range follows the prediction of the simplest ion−dipole capture model. Use of different buffer gas collisional cooling in both the ion source and the RET reveals the effects of both translational and vibrational energy of the N2+ ions.

Branching and rate coefficients of the HBr+ + HBr reaction through the isotope-resolved REMPI technique

Co-reporter:Andrey E. Belikov, Mark A. Smith

International Journal of Mass Spectrometry 2005 Volume 246(1–3) pp:43-48

Publication Date(Web):1 November 2005

DOI:10.1016/j.ijms.2005.05.007

The charge-, atom- and proton-transfer channels of the HBr+ + HBr reaction have been studied at low temperature in an HBr + Ar free jet. Exploring ordinary HBr gas with the natural H79Br + H81Br (1:1) isotope abundance, the H79Br+ and H81Br+ ions in specific spin-orbit and vibrational states were prepared by resonance multiphoton ionisation in an isotope-selective manner that gave the opportunity to analyse reaction branching ratios and mechanisms.

State-specific low temperature reactions (HBr+, DBr+) [2Πi,v] + (H2, D2): channels and rates

Co-reporter:Andrey E Belikov, Mark A Smith

Chemical Physics Letters 2004 Volume 387(1–3) pp:7-11

Publication Date(Web):21 March 2004

DOI:10.1016/j.cplett.2003.12.129

Abstract

The channels of the HBr⁺(Π_i,v) + D₂ and DBr⁺(Π_i,v) + H₂ ion–molecule reactions were investigated in a state-selective manner at low temperatures in a free jet. The selected spin–orbit and vibrational states of the ions were prepared by resonance-enhanced multiphoton ionisation. All three energetically accessible channels of the reactions were under consideration using time-of-flight mass spectrometry. The dependence of the rate coefficient of the atom transfer channel versus reaction energy appears to be common to all ion–molecule pairs studied here and previously: HBr⁺ + H₂, HBr⁺ + D₂, DBr⁺ + H₂, DBr⁺ + D₂.