Browsing Τμήμα Χημείας / Department of Chemistry by Author "Nicolaïdes, Andrew N."
Now showing items 21-36 of 36
-
Article
Hula-twist photoisomerization of a styrene derivative examined by argon-matrix-infrared-spectroscopic method
Nakane, N.; Nicolaïdes, Andrew N.; Tomioka, H.; Asato, A. E.; Liu, R. S. H. (2006)IR spectra of α-cyano- o -fluorocinnamonitrile, its vinyl deuterated analogue and the corresponding photoproducts were recorded under Ar matrix isolation conditions (13K). An analysis of the IR spectra, assisted by ...
-
Article
Is the most stable gas-phase isomer of the benzenium cation a face-protonated π-complex?
Glukhovtsev, M. N.; Pross, A.; Nicolaïdes, Andrew N.; Radom, L. (1995)The recent suggestion, based on gas-phase experimental data, that the most stable isomer of protonated benzene has a face-protonated π-complex structure is not supported by our detailed computations which indicate that the ...
-
Article
Lipidomics and free radical modifications of lipids
Chatgilialoglu, C.; Ferreri, C.; Hermetter, A.; Lacote, E.; Mihaljević, B.; Nicolaïdes, Andrew N.; Siafaka-Kapadai, Athanassia (2008)The free-radical-induced modification of biologically relevant molecules is an active field of interdisciplinary research, spanning from chemistry to biochemistry, biology and medicine. Lipid modifications are also attracting ...
-
Article
o-Phenylene halocarbenonitrenes and o-phenylene chlorocarbenocarbene: A combined experimental and computational approach
Enyo, T.; Arai, N.; Nakane, N.; Nicolaïdes, Andrew N.; Tomioka, H. (2005)Computations find that o-phenylene(halo)carbenonitrenes 2-XN, X = F, Cl, Br, have quinoidal singlet biradical ground states such as the parent o-phenylenecarbenonitrene (2-HN). Compared to the parent 2-HN, halogen substitution ...
-
Article
Of ortho-conjugatively linked reactive intermediates: The cases of ortho-phenylene-(bis)nitrene, -carbenonitrene, and -(bis)carbene
Nicolaïdes, Andrew N.; Nakayama, T.; Yamazaki, K.; Tomioka, H.; Koseki, S.; Stracener, L. L.; McMahon, R. J. (1999)ortho-Phenylene-bisnitrene (2) and -carbenonitrene (3) were generated in an inert matrix at low temperature, characterized by IR spectroscopy, and identified with the help of DFT calculations. Their thermal and photochemical ...
-
Article
Optical and infrared properties of a series of pyramidalized olefin Pt-complexes - DFT study
Oprea, C. I.; Moscalu, F.; Dumbravǎ, A.; Ioannou, Savvas; Nicolaïdes, Andrew N.; Gîrţu, M. A. (2009)We report Density Functional Theory (DFT) calculations providing the geometrical and electronic structures, as well as the vibrational and optical properties of the homologous series of Pt-pyramidalized olefin complexes ...
-
Article
p-phenylenecarbenonitrene and its halogen derivatives: How does resonance interaction between a nitrene and a carbene center affect the overall electronic configuration?
Nicolaïdes, Andrew N.; Enyo, T.; Miura, D.; Tomioka, H. (2001)A series of para-conjugatively coupled phenylenecarbenonitrenes {(4-nitrenophenyl)methylene (3a), (4-nitrenophenyl)fluoromethylene (3b), (4-nitrenophenyl)chloromethylene (3c), and (4-nitrenophenyl)bromomethylene (3d)} were ...
-
Article
Phenyl radical, cation, and anion. The triplet-singlet gap and higher excited states of the phenyl cation
Nicolaïdes, Andrew N.; Smith, D. M.; Jensen, F.; Radom, L. (1997)High-level ab initio molecular orbital calculations have been carried out for the phenyl cation (1), the phenyl radical (2), and the phenyl anion (3). Our best estimate for the heat of formation (ΔH(f298)) of the phenyl ...
-
Article
Photochemistry of an azido-functionalized cryptand: Controlling the reactivity of an extremely long-lived singlet aryl nitrene by complexation to alkali cations
Bucher, G.; Tönshoff, C.; Nicolaïdes, Andrew N. (2005)Photolysis of the cryptand 1, bearing an intraannular azido substituent, results in a complex photochemistry. Low-temperature photolysis yields the triplet nitrene 32, which has been characterized by EPR spectroscopy. Small ...
-
Article
Relative stabilities and hydride affinities of silatropylium and silabenzyl cations and their isomers. Comparison with the carbon analogues tropylium and benzyl cations
Nicolaïdes, Andrew N.; Radom, L. (1996)High-level ab initio calculations on silatropylium (1-Si) and silabenzyl (2-Si) cations and seven of their low-lying isomers (3-8), as well as on their carbon analogues, tropylium (1-C) and benzyl (2-C) cations, are reported. ...
-
Article
Ring opening of the cyclopropylcarbinyl radical and its N- and O- substituted analogues: A theoretical examination of very fast unimolecular reactions
Smith, D. M.; Nicolaïdes, Andrew N.; Golding, B. T.; Radom, L. (1998)High level ab initio molecular orbital calculations have been used to examine the ring opening of the cyclopropylcarbinyl radical and its heterosubstituted analogues. The applicability of various theoretical techniques to ...
-
Article
Seven-Membered Ring or Phenyl-Substituted Cation? Relative Stabilities of the Tropylium and Benzyl Cations and Their Silicon Analogs
Nicolaïdes, Andrew N.; Radom, L. (1994)
-
Article
A simple failing of G2 theory: Heats of combustion
Nicolaïdes, Andrew N.; Radom, L. (1994)G2 theory, which is normally very reliable for the prediction of reaction thermochemistry, is shown to be quite unsuitable for the prediction of heats of combustion. This arises because of significant errors in G2 energies ...
-
Article
Singlet hydrocarbon carbenes with high barriers toward isomerization: A computational investigation
Nicolaïdes, Andrew N. (2003)A prerequisite for a stable singlet hydrocarbon carbene is the existence of high barriers toward isomerization. Four derivatives of cyclopentylidene (1-4) with rigid and varying carbon cages are examined computationally ...
-
Article
Synthesis and Study of the (Ph3P)2Pt Complexes of Three Members of a Series of Highly Pyramidalized Alkenes
Nicolaïdes, Andrew N.; Smith, J. M.; Kumar, A.; Barnhart, D. M.; Borden, W. T. (1995)The (Ph3P)2Pt complexes (3) of three members of a homologous series of tricyclo[3.3.n.03,7]alk-3(7)-enes (2a-c) have been prepared by allowing these highly pyramidalized alkenes to displace ethylene from (Ph3P)2PtC2H4. The ...
-
Article
A theoretical study of chlorine atom and methyl radical addition to nitrogen bases: Why do Cl atoms form two-center - Three electron bonds whereas CH3 radicals form two-center - Two-electron bonds?
McKee, M. L.; Nicolaïdes, Andrew N.; Radom, L. (1996)Ab initio molecular orbital calculations have been carried out on a series of adducts between chlorine atom and NH3, NMe3, NCl3, HN=CH2, and pyridine, and between methyl radical and HN=CH2 and pyridine. A two-center-three-electron ...