P B Armentrout

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In this review, noncovalent interactions of ions with neutral molecules are discussed. After defining the scope of the article, which excludes anionic and most protonated systems, methods associated with measuring thermodynamic information for such systems are briefly recounted. An extensive set of tables detailing available thermodynamic information for(More)
An evaluation of the extended kinetic method with full entropy analysis was conducted using RRKM theory to simulate data for collision-induced dissociation under single-collision conditions. A rigorous method for analyzing kinetic method data, orthogonal distance regression, is introduced and compared with previous methods in the literature. The results(More)
The deamidation and dehydration products of Na+(L), where L = asparagine (Asn), glutamine (Gln), aspartic acid (Asp), and glutamic acid (Glu), are examined in detail utilizing collision-induced dissociation (CID) with Xe in a guided ion beam tandem mass spectrometer (GIBMS). Results establish that the Na+(L) complexes decompose upon formation in our dc(More)
The binding of Na (+) to arabinose (Ara), xylose (Xyl), glucose (Glc), and galactose (Gal) is examined in detail by studying the collision-induced dissociation (CID) of the four sodiated monosaccharide complexes with Xe using a guided ion beam tandem mass spectrometer (GIBMS). Analysis of the energy-dependent CID cross-sections provides 0 K sodium cation(More)
Deamidation at asparagine residues, a spontaneous post-translational modification in proteins, plays a significant role in various biological processes and degenerative diseases. In the current work, we present a full description of the deamidation process as well as other key fragmentations (dehydration, peptide bond cleavage, and loss of 2 NH3) from(More)
The interactions of cesium cations with five amino acids (AA) including glycine (Gly), proline (Pro), serine (Ser), threonine (Thr), and cysteine (Cys) are examined in detail. Experimentally, the bond dissociation energies (BDEs) are determined using threshold collision-induced dissociation of the Cs(+)(AA) complexes with xenon in a guided ion beam tandem(More)
The binding of Na+ to aspartic acid (Asp), glutamic acid (Glu), asparagine (Asn), and glutamine (Gln) is examined in detail by studying the collision-induced dissociation (CID) of the four sodiated amino acid complexes with Xe using a guided ion beam tandem mass spectrometer (GIBMS). Analysis of the energy-dependent CID cross sections provides 0 K sodium(More)
Thermochemistry determined from careful analysis of the energy dependence of cross sections for collision-induced dissociation (CID) reactions has primarily come from the primary dissociation channel. Higher order dissociations generally have thresholds measured to be higher than the thermodynamic limit because of the unknown internal and kinetic energy(More)
We present a full molecular description of fragmentation reactions of protonated diglycine (H(+)GG) by studying their collision-induced dissociation (CID) with Xe using a guided ion beam tandem mass spectrometer (GIBMS). Analysis of the kinetic energy-dependent CID cross sections provides the 0 K barriers for the sequential H(2)O+CO and CO+NH(3) losses from(More)
We present a full computational description of the fragmentation reactions of protonated diglycine (H(+)GG). Relaxed potential energy surface scans performed at B3LYP/6-31 G(d) or B3LYP/6-311 + G(d,p) levels are used to map the reaction coordinate surfaces and identify the transition states (TSs) and intermediate reaction species for seven reactions(More)