@article{KleinpeterBalciYaparetal.2012,
  author    = {Kleinpeter, Erich and Balci, Kubilay and Yapar, G. and Akkaya, S. and Akyuz, S. and Koch, Andreas},
  title     = {A conformational analysis and vibrational spectroscopic investigation on 1,2-bis(o-carboxyphenoxy) ethane molecule},
  year      = {2012},
  abstract  = {The minima on the potential energy surface of 1,2-bis(o-carboxyphenoxy) ethane (CPE) molecule in its electronic ground state were searched by a molecular dynamics simulation performed with MM2 force field. For each of the found minimum-energy conformers, the corresponding equilibrium geometry, charge distribution, HOMO-LUMO energy gap, force field, vibrational normal modes and associated IR and Raman spectral data were determined by means of the density functional theory (DFT) based electronic structure calculations carried out by using B3LYP method and various Pople- style basis sets. The obtained theoretical data confirmed the significant effects of the intra- and inter-molecular hydrogen bonding interactions on the conformational structure, force field, and group vibrations of the molecule. The same data have also revealed that two of the determined stable conformers, both of which exhibit pseudo-crown structure, are considerably more favorable in energy to the others and accordingly provide the major c ntribution to the experimental spectra of CPE. In the light of the improved vibrational spectral data obtained within the "SQM FF" methodology and "Dual Scale Factors" approach for the monomer and dimer forms of these two conformers, a reliable assignment of the fundamental bands observed in the experimental room-temperature IR and Raman spectra of the molecule was given, and the sensitivities of its group vibratb20s to conformation, substitution and dimerization were discussed.},
  language  = {en}
}
@article{BalciYaparAkkayaetal.2012,
  author    = {Balci, Kubilay and Yapar, G. and Akkaya, Y. and Akyuz, S. and Koch, Andreas and Kleinpeter, Erich},
  title     = {A conformational analysis and vibrational spectroscopic investigation on 1,2-bis(o-carboxyphenoxy) ethane molecule},
  series = {Vibrational spectroscopy : an international journal devoted to applications of infrared and raman spectroscopy},
  volume    = {58},
  journal   = {Vibrational spectroscopy : an international journal devoted to applications of infrared and raman spectroscopy},
  number    = {1-2},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0924-2031},
  doi       = {10.1016/j.vibspec.2011.11.011},
  pages     = {27 -- 43},
  year      = {2012},
  abstract  = {The minima on the potential energy surface of 1,2-bis(o-carboxyphenoxy)ethane (CPE) molecule in its electronic ground state were searched by a molecular dynamics simulation performed with MM2 force field. For each of the found minimum-energy conformers, the corresponding equilibrium geometry, charge distribution, HOMO-LUMO energy gap, force field, vibrational normal modes and associated IR and Raman spectral data were determined by means of the density functional theory (DFT) based electronic structure calculations carried out by using B3LYP method and various Pople-style basis sets. The obtained theoretical data confirmed the significant effects of the intra- and inter-molecular hydrogen bonding interactions on the conformational structure, force field, and group vibrations of the molecule. The same data have also revealed that two of the determined stable conformers, both of which exhibit pseudo-crown structure, are considerably more favorable in energy to the others and accordingly provide the major contribution to the experimental spectra of CPE. In the light of the improved vibrational spectral data obtained within the "SQM FF" methodology and "Dual Scale Factors" approach for the monomer and dimer forms of these two conformers, a reliable assignment of the fundamental bands observed in the experimental room-temperature IR and Raman spectra of the molecule was given, and the sensitivities of its group vibrations to conformation, substitution and dimerization were discussed.},
  language  = {en}
}
@article{KramerKleinpeter2013,
  author    = {Kramer, Markus and Kleinpeter, Erich},
  title     = {A conformational study of N-acetyl glucosamine derivatives utilizing residual dipolar couplings},
  issn      = {1090-7807},
  year      = {2013},
  language  = {en}
}
@article{KramerKleinpeter2011,
  author    = {Kramer, Markus and Kleinpeter, Erich},
  title     = {A conformational study of N-acetyl glucosamine derivatives utilizing residual dipolar couplings},
  series = {Journal of magnetic resonance},
  volume    = {212},
  journal   = {Journal of magnetic resonance},
  number    = {1},
  publisher = {Elsevier},
  address   = {San Diego},
  issn      = {1090-7807},
  doi       = {10.1016/j.jmr.2011.06.029},
  pages     = {174 -- 185},
  year      = {2011},
  abstract  = {The conformational analyses of six non-rigid N-acetyl glucosamine (NAG) derivatives employing residual dipolar couplings (RDCs) and NOEs together with molecular dynamics (MD) simulations are presented. Due to internal dynamics we had to consider different conformer ratios existing in solution. The good quality of the correlation between theoretically and experimentally obtained RDCs show the correctness of the calculated conformers even if the ratios derived from the MD simulations do not exactly meet the experimental data. If possible, the results were compared to former published data and commented.},
  language  = {en}
}
@misc{KramerKleinpeter2011,
  author    = {Kramer, Markus and Kleinpeter, Erich},
  title     = {A conformational study of N-acetyl glucosamine derivatives utilizing residual dipolar couplings (vol 212, pg 174, 2011)},
  series = {Journal of magnetic resonance},
  volume    = {213},
  journal   = {Journal of magnetic resonance},
  number    = {1},
  publisher = {Elsevier},
  address   = {San Diego},
  issn      = {1090-7807},
  doi       = {10.1016/j.jmr.2011.09.017},
  pages     = {210 -- 211},
  year      = {2011},
  language  = {en}
}
@article{ThomasKleinpeter2005,
  author    = {Thomas, Steffen and Kleinpeter, Erich},
  title     = {A novel empirical approach for the structure elucidation of disilanes by empirical estimation of their Si-29 chemical shifts},
  issn      = {0022-2860},
  year      = {2005},
  abstract  = {In C-13 NMR spectroscopy, there are many empirical methods for fast and exact computation of C-13 chemical shifts; comparable procedures for Si-29 NMR chemical shifts are not existing or are older than 20 years. On basis of the largest database of Si-29 chemical shifts available, along this paper a relatively simple procedure for the similarly exact calculation of the Si-29 chemical shifts of disilanes (average margin of error ca. 3.7 ppm) is given. (c) 2005 Elsevier B.V. All rights reserved},
  language  = {en}
}
@article{DrexlerGrotjahnKleinpeteretal.1999,
  author    = {Drexler, Hans-Joachim and Grotjahn, Manuela and Kleinpeter, Erich and Holdt, Hans-J{\"u}rgen},
  title     = {A novel polymeric disilver(I) complex containing both macrocyclic- and linear-coordinate silver(I) centres : [Ag-2(mn-15S(2)O(3))](infinity)(ClO4)(2 infinity) (mn-15S(2)O(3) = maleonitrile-dithia[15]crown-5)},
  year      = {1999},
  language  = {en}
}
@article{BalciKochKleinpeter2009,
  author    = {Balci, Kubilay and Koch, Andreas and Kleinpeter, Erich},
  title     = {A theoretical IR spectroscopic study based on DFT calculations for free mn-15S(2)O(3) maleonitrile-dithiacrown ether compound},
  issn      = {0022-2860},
  doi       = {10.1016/j.molstruc.2008.08.027},
  year      = {2009},
  abstract  = {The theoretically possible stable conformers of free mn-15S2O3 maleonitrile-dithiacrown ether molecule were searched by means of a conformational study which consists of molecular dynamics and energy minimization calculations performed with MM2 force field and successive geometry optimization + frequency calculations performed first at B3LYP/3- 21G and then at B3LYP/6-31G(d) levels of theory. The obtained calculation results have clearly indicated that the free molecule in electronic ground state is very flexible and accordingly has many possible stable conformers of different conformational properties at room temperature; among them, the one having a macrocyclic ring structure in which all of the ether units oriented toward the center of the ring was determined the energetically most preferable conformer. In addition, the equilibrium geometrical parameters, vibrational normal modes and associated IR spectral data of the determined most stable three conformers of the molecule were calculated at B3LYP/6-31+G(d) and B3LYP/6-31++G(d,p) levels of theory. A successful assignment of the fundamental bands observed in the recorded experimental solid phase and solution phase IR spectra of the molecule was achieved in the light of the theoretical data obtained from these DFT calculations. To fit the calculated harmonic wavenumbers to the experimental ones, two different scaling procedures, referred to as "Scaled Quantum Mechanical Force Field (SQM FF) methodology" and "Scaling wavenumbers with empirical dual scale factors", were proceeded independently.},
  language  = {en}
}
@article{KleinpeterKlod2004,
  author    = {Kleinpeter, Erich and Klod, Sabrina},
  title     = {Ab initio calculation of the anisotropic/ring current effects of amino acid residues to locate the position of substrates in the binding site of enzymes},
  year      = {2004},
  abstract  = {The ring current effects of aromatic moieties and the anisotropic effects of the C=O and C-X (X = C, N, S) bonds and of the NH=C(NH2)-NH- moiety in the side chains of amino acid residues of proteins were ab initio calculated based on nuclear independent chemical shieldings as employed by P.v.R. Schleyer. Hereby, quantitative information about the spatial extension, sign and scope of the corresponding ring current/anisotropic effects was obtained and they were visualized as iso-chemical-shielding-surfaces. Examining this quantitative information compared with experimental NMR chemical shifts, the role of the corresponding amino acid residues in binding substrates in the binding site of enzymes was studied. (C) 2004 Elsevier B.V. All rights reserved},
  language  = {en}
}
@article{KochMikhovaKleinpeter2004,
  author    = {Koch, Andreas and Mikhova, Bozhana and Kleinpeter, Erich},
  title     = {Ab initio MP2/GIAO/NBO study of the delta-syn-axial effect in C-13 NMR spectroscopy},
  issn      = {0022-2860},
  year      = {2004},
  abstract  = {The C-13 chemical shifts of 20 rigid bicyclic compounds have been calculated with ab initio HF and MP2 methods. The calculations showed very good reproducibility of the experimental values. The molecular orbital interactions in the rigid, nearly planar delta-syn-axial fragments in the isomeric groups of norbornane derivatives 1.x-4.x were studied in detail and were employed to explain the deshielding delta-syn-axial effect in C-13 NMR spectroscopy. (C) 2004 Elsevier B.V. All rights reserved},
  language  = {en}
}