Premium
Velocity distributions of analyte molecules in matrix‐assisted laser desorption from computer simulations
Author(s) -
Zhigilei Leonid V.,
Garrison Barbara J.
Publication year - 1998
Publication title -
rapid communications in mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.528
H-Index - 136
eISSN - 1097-0231
pISSN - 0951-4198
DOI - 10.1002/(sici)1097-0231(19980930)12:18<1273::aid-rcm257>3.0.co;2-e
Subject(s) - analyte , chemistry , plume , matrix (chemical analysis) , molecule , maxwell–boltzmann distribution , thermal desorption , analytical chemistry (journal) , molecular physics , desorption , plasma , thermodynamics , physics , chromatography , organic chemistry , adsorption , quantum mechanics
The mass dependence of the velocity distributions of analyte molecules in matrix‐assisted laser desorption is analyzed based on the results of molecular dynamics simulations. The spread of the velocities along the direction of the flow is found to be independent of the mass of the analyte molecules and to reflect the entrainment of the analyte molecules in the expanding matrix. The radial velocity distributions for both matrix molecules and analyte molecules of different masses, on the other hand, fit well to a Maxwell–Boltzmann distribution with the same temperature, suggesting the association of the spread in the radial velocities with the thermal motion in the plume. A consistent analytical description of the complete velocity distribution for matrix molecules and analyte molecules of different masses is proposed based on the approximation of a range of stream velocities and a single temperature in the ejected plume. © 1998 John Wiley & Sons, Ltd.