Research Activities
and selected papers
¨ Vibrational
Spectroscopy
The project includes FT-IR and FT-Raman
investigation of various organic and inorganic compounds. The spectra are
interpreted by the aid of quantum chemical calculations, using the scaled
quantum mechanical (SQM) method of Pulay. This means a computation of the
molecular geometry and harmonic force field of the target by an advanced
quantum chemical method (B3-LYP in conjunction with a valence double- or
triple-zeta basis set), scaling of the harmonic force field to correct for
anharmonicity and other deficiencies of the computations, and a determination
of the total energy distribution of the fundamentals.
A. Kovács, A.S. Booij, R.J.M. Konings:
High-temperature infrared spectra of LaCl3, LaBr3 and LaI3.
Chemical
Physics Letters,
268 (1997) 207-212. Abstract
A. Kovács, V. Izvekov, G. Keresztury, G. Pongor: Vibrational analysis of
2-nitrophenol. A joint FT-IR, FT-Raman and scaled quantum mechanical study.
Chemical Physics, 238 (1998) 231-243. Abstract
A. Kovács, G. Keresztury, V. Izvekov: Intramolecular hydrogen bonding in
2-nitrorezorcinol. A combined FT-IR, FT-Raman and computational study.
Chemical
Physics, 253 (2000)
193-204. Abstract
A. Kovács, V. Izvekov, K. Zauer, K. Ohta: Strong intramolecular hydrogen bonding
and molecular vibrations of 9-hydroxyphenalen-1-one.
The
Journal of Physical Chemistry A, 105 (2001) 5000-5009. Abstract
A. Szabó, V.I.
Češljević, A. Kovács: Tautomerism, hydrogen
bonding and vibrational properties of 4-acetyl-3(5)-amino-5(3)-methylpyrazole.
Chemical
Physics, 270 (2001)
67-78. Abstract
A. Kovács,
R.J.M. Konings: Trimer Formation of AgI. A Gas-Phase FT-IR and Theoretical
Study.
Journal
of Molecular Structure, 643 (2002) 155-160. Abstract
D. Nemcsok, A. Kovács, K.
Mészáros-Szécsényi, V. M. Leovac: Vibrational spectroscopic and theoretical study
of 3,5-dimethyl-1-thiocarboxamide pyrazole (L) and the complexes Co2L2Cl4,
Cu2L2Cl4 and Cu2L2Br2.
Chemical
Physics, 328 (2006)
85-92. Abstract
A. Kovács, V. Izvekov,
G. Keresztury, C. J. Nielsen, P. Klæboe: Vibrational spectroscopic study
of 2-fluorophenol and 2,3,5,6-tetrafluorohydroquinone.
Chemical
Physics,
335 (2007) 205-214. Abstract
A. Kovács, B. Nyerges, V. Izvekov: Vibrational analysis of
N-acetyl-α-d-glucosamine and
β-d-glucuronic acid. Journal of Physical Chemistry B, 112 (2008) 5728-5735. Abstract
P. Pogány, A. Kovács, K. Mészáros
Szécsényi, V. M.
Leovac: FT-IR and theoretical study of 3,5-dimethyl-1H-pyrazole-1-carboxamidine (L) and the
complexes CoL2(H2O)2(NO3)2
and NiL2(H2O)2(NO3)2. Spectrochimica
Acta A, 71 (2008) 1466-1473. Abstract
A. Kovács, A. Yu. Ivanov: Vibrational analysis of a-d-glucose trapped in Ar matrix. Journal of Physical Chemistry B, 113 (2009) 2151-2159. Abstract
C. P. Groen, A. Kovács: Matrix-isolation FT-IR
study of (CsBr)n and (CsI)n (n=1-3). Vibrational Spectroscopy, 54 (2010) 30-34. Abstract
¨ Weak Interactions
The molecular geometry of various molecules (recently
primarily carbohydrates) possessing weak interactions are investigated by
quantum chemical calculations. The main focus of this research is on
intramolecular hydrogen bonding interactions. The characteristics of the weak
interactions are explored by analysis of the structure and charge distribution
in the molecular system.
A. Kovács, I. Macsári, I. Hargittai:
Intramolecular hydrogen bonding in fluorophenol derivatives: 2-fluorophenol,
2,6-difluorophenol and 2,3,5,6-tetrafluorohydroquinone.
The
Journal of Physical Chemistry A, 103 (1999) 3110-3114. Abstract
A. Kovács, A. Szabó, D. Nemcsok, I.
Hargittai: Blue-shifting C–H…O (X=O, halogen) hydrogen bonds in the
dimers of formaldehyde derivatives.
The
Journal of Physical Chemistry A, 106 (2002) 5671-5678. Abstract
A.
Kovács, A.
Szabó,
Accounts
of Chemical Research,
35 (2002) 887-894. Abstract
V. Horváth, Z.
Varga, A. Kovács: Long-range effects in oligopeptides. A
theoretical study of the b-sheet structure of Glyn (n = 2 - 10).
The
Journal of Physical Chemistry A, 108 (2004) 6869-6873. Abstract
B.
Nyerges, A. Kovács: Density functional study of the
conformational space of 4C1 d-glucuronic acid.
The
Journal of Physical Chemistry A, 109 (2005) 892-897. Abstract
A.
Kovács, Z.
Varga: Halogen acceptors in hydrogen bonding.
Coordination
Chemistry Reviews,
250 (2006) 710-727. Abstract
B. Nyulasi, A. Kovács:
Theoretical study of F-–(H2)n and Cl-–(H2)n
(n = 1-8) anion complexes.
Chemical
Physics Letters,
426 (2006) 26-29. Abstract
¨ Structure and bonding of
coordination compounds
Structural and bonding analysis of transition
metal and other donor-acceptor complexes using advanced computational
techniques. The project includes analysis of the binding energy of the ligand,
the molecular geometry and various bonding properties (natural charges,
topological properties of the electron density distribution, donation and
backdonation) of the complex.
A. Kovács, G. Frenking: Bonding interactions of a molecular pair of tweezers with
transition metals. Theoretical study of bis(h2-alkyne) complexes of copper (I),
silver (I) and gold (I).
Organometallics, 18 (1999) 887-894. Abstract
D.S. Nemcsok, A. Kovács, V.M. Rayón, G. Frenking:
Nature of the Transition Metal-(h2-H2)
Bond in TM(CO)3X2(h2-H2) (TM = Cr, Mo, W; X = CO, PH3,
PCl3, PMe3) Complexes.
Organometallics, 21 (2002) 5803-5809. Abstract
M. Lein, A. Szabó, A. Kovács,
G. Frenking: Energy decomposition analysis of the chemical bond in main group
and transition metal compounds.
Faraday
Discussions, 124
(2003) 365-378. Abstract
A. Kovács, C.
Esterhuysen, G. Frenking: The nature of the chemical bond revisited: An energy
partitioning analysis of nonpolar bonds.
Chemistry
- A European Journal,
11 (2005) 1813-1825. Abstract
A. Kovács, D.
Nemcsok, G. Pokol, K. Mészáros Szécsényi, V. M.
Leovac, Ž. K. Jaćimović, I. R. Evans, J. A. K. Howard, Z. D.
Tomić, G. Giester: Structural, spectroscopic and computational studies of
the HgL2Cl2 complex (L=3,5-dimethyl-1-thiocarboxamide
pyrazole) and the crystal structure of L.
New
Journal of Chemistry,
29 (2005) 833-840. Abstract
A. Kovács, K.
Mészáros Szécsényi, V.M. Leovac, Z. D. Tomić, G. Pokol: Synthesis under self-controlled
reaction conditions: reaction of tetraamminezinc(II) chloride with
3,5-dimethyl-1-thiocarboxamide pyrazole.
Journal of
Organometallic Chemistry, 692 (2007)
2582-2592. Abstract
A. Kovács:
Theoretical study of the strong intramolecular hydrogen bond and metal-ligand
interactions in group 10 (Ni, Pd, Pt) bis(dimethylglyoximato) complexes
Journal of
Organometallic Chemistry, 692 (2007) 5383-5389.
Abstract
¨ F-elements (lanthanides,
actinides)
Structural and bonding analysis of lanthanide
and actinide compounds using sophisticated quantum chemical techniques. The
project is carried out in cooperation with the
A. Kovács: Theoretical study of rare earth trihalide dimers Ln2X6
(Ln=La, Dy; X=F, Cl, Br, I).
Chemical
Physics Letters,
319 (2000) 238-246. Abstract
P. Groen, A. Oskam, A.
Kovács: Theoretical study of mixed LiLnX4 (Ln=La, Dy;
X=F, Cl, Br, I) rare earth/alkali halide complexes.
Inorganic
Chemistry, 39
(2000) 6001-6008. Abstract
A.
Kovács, R.J.M. Konings: Structure and Vibrations of Lanthanide
Trihalides. An Assessment of Experimental and Theoretical Data.
Journal
of Physical and Chemical Reference Data, 33 (2004) 377-404. Abstract
R.J.M. Konings, A. Kovács:
Thermodynamic properties of the lanthanide(III) halides. Handbook on Physics
and Chemistry of Rare Earth, Chapter 213, K. A. Gschneidner, Jr., J.-C. G.
Bünzli, V. K. Pecharsky, Eds., Elsevier,
A. Kovács, R.J.M. Konings: A
theoretical study of the structure and bonding of UOX4 (X=F, Cl, Br,
I) molecules. The importance of inverse trans influence.
ChemPhysChem, 7 (2006) 455-462. Abstract
A.
Kovács, R.J.M. Konings: Molecular structure and thermodynamic
properties of the gaseous ThC2 and ThC4 species.
Journal of Nuclear
Materials,
372 (2008) 391-393 Abstract
A. Kovács, R.J.M. Konings, J. Raab, L. Gagliardi: A
theoretical study of AmOn and CmOn (n = 1, 2). Physical
Chemistry Chemical Physics, 10 (2008) 1114-1118. Abstract
A. Kovács, R.J.M. Konings: Computed vibrational
frequencies of actinide oxides AnO0/+/2+ and AnO20/+/2+
(An = Th, Pa, U, Np, Pu, Am, Cm). Journal
of Physical Chemistry A, 115(24) (2011) 6646-6656. Abstract