A. Hopkinson

发表

A theoretical study of substituent effects in cyclopropyl and isopropyl cations: Strain energies in cyclopropyl cations and proton affinities of propenes and ethylenes

A. C. Hopkinson, M. Lien, A. Hopkinson, 1985 .

Hydrogen atom transfer in metal ion complexes of the glutathione thiyl radical

V. Ryzhov, Michael Lesslie, K. Siu, 2017, International Journal of Mass Spectrometry.

Experimental and theoretical studies of the basicity and proton affinity of SiF4 and the structure of SiF4H+

Y. Ling, D. Bohme, A. C. Hopkinson, 1999 .

Structures of [GPGG + H – H2O]+ and [GPGG + H – H2O – NH CH2]+ ions; evidence of rearrangement prior to dissociation

J. Martens, G. Berden, J. Oomens, 2019, International Journal of Mass Spectrometry.

Imidazolone formation from protonated tetrapeptides: Effects of replacing a glycine by an alanine or proline residue

K. Siu, A. C. Hopkinson, J. Lau, 2019, International Journal of Mass Spectrometry.

Differential ion mobility separation of isomers for threshold collision-induced dissociation measurements

V. Romanov, K. Siu, A. C. Hopkinson, 2013 .

Structures of the a2 ions of Ala-Ala-Ala and Phe-Phe-Phe

Q. Hao, J. Oomens, K. Siu, 2012 .

Fragmentations of protonated cyclic-glycylglycine and cyclic-alanylalanine

J. Oomens, K. Siu, A. C. Hopkinson, 2012 .

Doubly charged protonated a ions derived from small peptides.

K. Siu, A. C. Hopkinson, Junfang Zhao, 2011, Physical chemistry chemical physics : PCCP.

Structure of the [M + H - H2O]+ ion from tetraglycine: a revisit by means of density functional theory and isotope labeling.

J. Oomens, M. V. van Stipdonk, K. Siu, 2011, The journal of physical chemistry. A.

a2 Ion Derived from Triglycine: An N1-Protonated 4-Imidazolidinone

J. Oomens, K. Siu, C. Siu, 2010 .

Elucidation of fragmentation mechanisms of protonated Peptide ions and their products: a case study on glycylglycylglycine using density functional theory and threshold collision-induced dissociation.

Y. Ling, K. Siu, A. C. Hopkinson, 2003, Journal of the American Chemical Society.

Phosphate Migration versus the Loss of Phosphoric Acid in Protonated Phosphopeptides: A Computational Study.

K. Siu, J. Lau, A. Hopkinson, 2024, The journal of physical chemistry. B.

Theoretical Study on the Proton Affinity of Small Molecules Using Gaussian Basis Sets in the LCAO-MO-SCF Framework

I. Csizmadia, A. C. Hopkinson, K. Yates, 1968 .

Competitive activation of C-H and C-X bonds in reactions of Pt+ with CH3X (X=F,Cl): experiment and theory.

D. Bohme, Xiang Zhao, A. C. Hopkinson, 2008, Chemphyschem : a European journal of chemical physics and physical chemistry.

Proton affinities of methyl esters of N-acetylated amino acids

Y. Ling, Yuzhu Guo, I. Chu, 2002 .

Intrinsic Coordination Properties of Iron in FeO+: Kinetics at 294 .+-. 3 K for Gas-Phase Reactions of the Ground States of Fe+ and FeO+ with Inorganic Ligands Containing Hydrogen, Nitrogen, and Oxygen

V. Baranov, D. Bohme, A. C. Hopkinson, 1995 .

Carbocationic polymerization in the gas phase: polymerization of acetylene induced by BF2+

D. Bohme, M. Lien, L. Forte, 1990 .

An ab initio molecular orbital study of the deprotonation of amines

A. C. Hopkinson, M. Lien, A. Hopkinson, 1978 .

Ab Initio LCAO–MO–SCF Calculations on Formic Acid, Formate Ion, and Protonated Formic Acid

I. Csizmadia, A. C. Hopkinson, K. Yates, 1970 .

Characterization of the product ions from the collision-induced dissociation of argentinated peptides

I. Chu, K. Siu, A. C. Hopkinson, 2001, Journal of the American Society for Mass Spectrometry.

An ab initio molecular orbital study of the protonation of amines

Imre G. Csizmadia, I. Csizmadia, A. C. Hopkinson, 1974 .

An AB initio molecular orbital study of ten isomers on the C2SiH4 energy surface

A. C. Hopkinson, M. Lien, A. Hopkinson, 1981 .

A theoretical study of the effect of silicon substitution on hydrocarbon acidity

A. C. Hopkinson, M. Lien, A. Hopkinson, 1981 .

A non-empirical molecular orbital study of valence tautomers of C2H3N

I. Csizmadia, A. C. Hopkinson, K. Yates, 1977 .

Theoretical study of substituent effects on the acidity of the methyl group: Structure of anions CH2X−

A. C. Hopkinson, M. Lien, A. Hopkinson, 1980 .

An ab initio study of the AAc1 hydrolysis mechanism of formamide

I. Csizmadia, A. C. Hopkinson, A. Hopkinson, 1973 .

Nonempirical LCAO MO SCF Calculation on Acetylene, Vinylidene Carbene, and the Vinyl Cation

I. Csizmadia, A. C. Hopkinson, K. Yates, 1971 .

A theoretical investigation of α-substituents on the structure, proton affinities and inversion barriers of silyl anions

A. C. Hopkinson, M. Lien, A. Hopkinson, 1981 .

Substituent stabilisation energies in α-substituted carbocations CH2Z+, CH3CHZ+ and (CH3)2CZ+ where Z is NH2, PH2, AsH2, OH, SH and SeH

A. C. Hopkinson, C. F. Rodriquez, A. Hopkinson, 1987 .

ACID-CATALYZED REARRANGEMENTS OF CYCLOBUTANONES. IV. A NOVEL TOTAL SYNTHESIS OF A STEROID

L. Dao, E. Lee‐Ruff, A. Hopkinson, 1978 .

THE C4H5+ POTENTIAL ENERGY SURFACE. STRUCTURE, RELATIVE ENERGIES, AND ENTHALPIES OF FORMATION OF ISOMERS OF C4H5+

A. C. Hopkinson, C. F. Rodriquez, A. Cunje, 1996 .

Small-ring carbenes carrying a positive charge: the effects of substituting by CN in c-C4H3+

D. Bohme, A. C. Hopkinson, R. Milburn, 2000 .

Quantum chemical studies on electrophilic addition

I. Csizmadia, A. C. Hopkinson, K. Yates, 1977 .

An ab initio study of the structure of the 2-chloroethyl radical

I. Csizmadia, A. C. Hopkinson, M. Lien, 1980 .

Substituent effects in carbocations CX+, CHX+•, and CH2X+, and in singlet and triplet carbenes CHX. Proton affinities of singlet carbenes

M. Lien, A. Hopkinson, 1985 .

The thioformamidyl group as an α-substituent in carbocations

A. C. Hopkinson, D. Vučković, C. F. Rodriquez, 1995 .

Acid-catalysed hydrolysis of alkyl benzoates

A. Hopkinson, 1969 .

A theoretical study of the heats of formation of some small molecules using non-empirical wavefunctions

I. Csizmadia, A. C. Hopkinson, K. Yates, 1972 .

A study of complexes Mg(NH3)n+· and Ag(NH3)n+, where n = 1–8: competition between direct coordination and solvation through hydrogen bonding

G. Koyanagi, D. Bohme, K. Siu, 2000 .

Elimination of AgR (R = H, CH3, C6H5) from Collisionally-Activated Argentinated Amines

I. Chu, K. Siu, A. C. Hopkinson, 2000 .

Molecular orbital calculations of excited state cyclobutanone and its photocarbene

A. C. Hopkinson, E. Lee-Ruff, H. Lien, 1988 .

Structures of an* Ions Derived from Protonated Pentaglycine and Pentaalanine: Results from IRMPD Spectroscopy and DFT Calculations

J. Oomens, K. Siu, A. C. Hopkinson, 2013, Journal of The American Society for Mass Spectrometry.

Dissociative electron transfer of copper(ii) complexes of glycyl(glycyl/alanyl)tryptophan in vacuo: IRMPD action spectroscopy provides evidence of transition from zwitterionic to non-zwitterionic peptide structures.

J. Martens, G. Berden, J. Oomens, 2020, Physical chemistry chemical physics : PCCP.

Proton transfer reactions of HCO+ at 298 K

S. Tanner, D. Bohme, A. C. Hopkinson, 1979 .

Dissociation of the N-Cα bond and competitive formation of the [zn−H]•+ and [cn+2H]+ product ions in radical peptide ions containing tyrosine and tryptophan: The influence of proton affinities on product formation

Yuyong Ke, K. Siu, C. Siu, 2008, Journal of the American Society for Mass Spectrometry.

Dissociation of the N – C Bond and Competitive Formation of the [ z n – H ]

Yuyong Ke, K. Siu, C. Siu, 2022 .

A theoretical study of the effect of electron-withdrawing substituents on silicenium cations and silyl anions: Comparison with the analogous carbenium ions and carbanions

A. C. Hopkinson, M. Lien, A. Hopkinson, 1983 .

Experimental and theoretical studies of proton removal from propene

D. Bohme, A. C. Hopkinson, G. Mackay, 1978 .

A nonempirical molecular orbital study on the acidity of the carbon–hydrogen bond

P. Mezey, I. Csizmadia, A. C. Hopkinson, 1977 .

Infrared multiple-photon dissociation spectroscopy of tripositive ions: lanthanum-tryptophan complexes.

J. Oomens, K. Siu, A. C. Hopkinson, 2012, Inorganic chemistry.

Amination with Pd-NHC complexes: rate and computational studies involving substituted aniline substrates.

Ka Hou Hoi, R. Froese, A. C. Hopkinson, 2012, Chemistry.

Formation of abundant [Pb(H2O)]2+ by ligand-exchange reaction between [Pb(N2)n]2+ (n = 1-3) and H2O.

Tujin Shi, K. Siu, A. C. Hopkinson, 2005, The journal of physical chemistry. B.

Existence of doubly charged lead monohydrate: experimental evidence and theoretical examination.

Tujin Shi, D. Bohme, K. Siu, 2004, Journal of the American Chemical Society.

Hydrogen atom transfer in the radical cations of tryptophan-containing peptides AW and WA studied by mass spectrometry, infrared multiple-photon dissociation spectroscopy, and theoretical calculations

G. Berden, J. Oomens, Andrii Piatkivskyi, 2018, European Journal of Mass Spectrometry.

Isomerization versus dissociation of phenylalanylglycyltryptophan radical cations.

I. Chu, K. Siu, Xiaoyan Mu, 2017, Physical chemistry chemical physics : PCCP.

Radical-induced dissociation leading to the loss of CO2 from the oxazolone ring of [b5- H]˙(+) ions.

Yating Wang, K. Siu, A. C. Hopkinson, 2016, Physical chemistry chemical physics : PCCP.

Cysteine Radical/Metal Ion Adducts: A Gas-Phase Structural Elucidation and Reactivity Study.

V. Ryzhov, Michael Lesslie, P. Maître, 2016, ChemPlusChem.

Transnitrosylation products of the dipeptide cysteinyl-cysteine: an examination by tandem mass spectrometry and density functional theory.

A. C. Hopkinson, M. Butler, K. W. Michael Siu, 2016, Physical chemistry chemical physics : PCCP.

Investigation of Fragmentation of Tryptophan Nitrogen Radical Cation

Andrii Piatkivskyi, V. Ryzhov, K. Siu, 2015, Journal of The American Society for Mass Spectrometry.

Radical-induced, proton-transfer-driven fragmentations in [b(5)-H]˙(+) ions derived from pentaalanyl tryptophan.

Yating Wang, K. Siu, A. C. Hopkinson, 2015, Physical chemistry chemical physics : PCCP.

Fragmentation of peptide radical cations containing a tyrosine or tryptophan residue: structural features that favor formation of [x(n-1) + H]˙⁺ and [z(n-1) + H]˙⁺ ions.

Yating Wang, K. Siu, A. C. Hopkinson, 2014, The journal of physical chemistry. B.

Metal ion complexes with HisGly: comparison with PhePhe and PheGly.

G. Berden, J. Oomens, K. Siu, 2013, The journal of physical chemistry. A.

Fragmentation Chemistry of [Met-Gly]•+, [Gly-Met]•+, and [Met-Met]•+ Radical Cations

K. Siu, A. C. Hopkinson, J. Lau, 2013, Journal of The American Society for Mass Spectrometry.

Intramolecular hydrogen atom migration along the backbone of cationic and neutral radical tripeptides and subsequent radical-induced dissociations.

Minjie Xu, Q. Quan, I. Chu, 2012, Physical chemistry chemical physics : PCCP.

Elimination of water from the backbone of protonated tetraglycine

K. Siu, A. C. Hopkinson, J. Lau, 2012 .

Superhalogen plus anion KF3-: A recently discovered anion with the formula MXk+2-

A. C. Hopkinson, Seydina Lo, A. Hopkinson, 2011 .

Glutathione radical cation in the gas phase; generation, structure and fragmentation.

K. Siu, Junfang Zhao, A. Hopkinson, 2011, Organic & biomolecular chemistry.

A comparison of the fragmentation pathways of [Cu(II)(Ma)(Mb)]•2+ complexes where Ma and Mb are peptides containing either a tryptophan or a tyrosine residue.

Yuyong Ke, K. Siu, C. Siu, 2010, Rapid communications in mass spectrometry : RCM.

Dissociation of copper(II) ternary complexes containing cystine.

Yuyong Ke, K. Siu, A. C. Hopkinson, 2010, Physical chemistry chemical physics : PCCP.

Fragmentation of doubly charged metal–acetamide complexes: Second ionization energies and dissociation chemistries

Tujin Shi, K. Siu, A. C. Hopkinson, 2006 .

Carbonate, carbamate, urea, and guanidine as model species for functional groups in biological molecules A combined density functional theory and mass spectrometry examination of polysodiation and gas-phase dissociation

Tujin Shi, K. Siu, A. C. Hopkinson, 2005 .

Multiple substitution of protons by sodium ions in sodiated oligoglycines

Jeffrey C. Smith, K. Siu, A. C. Hopkinson, 2002 .

Formation of [M − nH + mNa](m−n)+ and [M − nH + mK](m−n)+ ions in electrospray mass spectrometry of peptides and proteins

K. Siu, A. C. Hopkinson, T. Shoeib, 2000, Journal of the American Society for Mass Spectrometry.

A POSSIBLE ORIGIN OF M - NH + MX(M-N)+ IONS (X = ALKALI METAL IONS) IN ELECTROSPRAY MASS SPECTROMETRY OF PEPTIDES

R. Fournier, I. Chu, K. Siu, 1999 .

Magnesium chemistry in the gas phase: calculated thermodynamic properties and experimental ion chemistry in H2–O2–N2 flames

D. Bohme, J. Goodings, A. C. Hopkinson, 1999 .

Negative hyperconjugation in methyl and silyl anions and its effect on the acidities of CH(4-n)Fn CH(4-n)C1n SiH(4-n)Fn and SiH(4-n)Cln

A. C. Hopkinson, C. F. Rodriquez, A. Hopkinson, 1993 .

A theoretical study of α‐substituted isopropyl and cyclopropyl anions

A. C. Hopkinson, M. McKinney, M. Lien, 1983 .

A theoretical study of the cyano and isocyano groups as α-substituents in alkyl carbanions and carbenium ions

A. C. Hopkinson, M. McKinney, M. Lien, 1983 .

A comparison of copper(I) and silver(I) complexes of glycine, diglycine and triglycine

K. Siu, A. C. Hopkinson, T. Shoeib, 2001 .

Substituent effects on the structures and strain energies of cyclopropenes

A. C. Hopkinson, M. Lien, A. Hopkinson, 1987 .

A theoretical study of the effects of silyl and methyl groups on acid-base reactions at oxygen, nitrogen and carbon

A. C. Hopkinson, M. Lien, A. Hopkinson, 1983 .

Fragmentation of Protonated Tripeptides: The Proline Effect Revisited

A. G. Harrison, A. Siu, K. Siu, 2004 .

Fragmentations of protonated arginine, lysine and their methylated derivatives: concomitant losses of carbon monoxide or carbon dioxide and an amine.

Yuyong Ke, K. Siu, A. C. Hopkinson, 2006, The journal of physical chemistry. A.

Conformation switching in gas-phase complexes of histidine with alkaline earth ions.

J. Oomens, K. Siu, C. Siu, 2009, The journal of physical chemistry. B.

Structure of the observable histidine radical cation in the gas phase: a captodative alpha-radical ion.

J. Oomens, Yuyong Ke, K. Siu, 2008, Angewandte Chemie.

Generation of [La(peptide)]3+ complexes in the gas phase: determination of the number of binding sites provided by dipeptide, tripeptide, and tetrapeptide ligands.

Tujin Shi, K. Siu, A. C. Hopkinson, 2007, The journal of physical chemistry. A.

Proposed nomenclature for peptide ion fragmentation

F. Tureček, H. Oh, V. Ryzhov, 2015 .

Structure and Reactivity of the Distonic and Aromatic Radical Cations of Tryptophan

J. Oomens, Andrii Piatkivskyi, V. Ryzhov, 2013, Journal of The American Society for Mass Spectrometry.

Dissociations of copper(II)-containing complexes of aromatic amino acids: radical cations of tryptophan, tyrosine, and phenylalanine.

Yuzhu Guo, Yuyong Ke, K. Siu, 2008, Physical chemistry chemical physics : PCCP.

Structures and Dissociation Products of Ce/Peptide Complexes: Competition between Coordination and Charge Delocalization.

Yating Wang, K. Siu, A. C. Hopkinson, 2019, The journal of physical chemistry. B.

Easily prepared air- and moisture-stable Pd-NHC (NHC=N-heterocyclic carbene) complexes: a reliable, user-friendly, highly active palladium precatalyst for the Suzuki-Miyaura reaction.

A. Lough, G. Chass, A. C. Hopkinson, 2006, Chemistry.

The extent and effects of peptide sequence scrambling via formation of macrocyclic b ions in model proteins

O. Krakovska, Yuzhu Guo, K. Siu, 2010, Journal of the American Society for Mass Spectrometry.

Optimization of parameters used in algorithms of ion-mobility calculation for conformational analyses.

Yuzhu Guo, K. Siu, C. Siu, 2009, The journal of physical chemistry. B.

How large is the [Fe(III)(protoporphyrin IX)]+ ion (hemin+) in the gas phase?

Yuzhu Guo, K. Siu, C. Siu, 2006, The journal of physical chemistry. B.

Gaseous bradykinin and its singly, doubly, and triply protonated forms: a first-principles study.

Yuzhu Guo, Yuzhu Guo, K. Siu, 2006, The journal of physical chemistry. B.