Artículos de revistas
Infrared Intensity Parameters Of The Diacetylene And Acidity Of Acetylenic Hydrogens
Registro en:
Spectrochimica Acta Part A: Molecular Spectroscopy. , v. 43, n. 3, p. 345 - 348, 1987.
5848539
10.1016/0584-8539(87)80115-0
2-s2.0-45949122681
Autor
Ramos M.N.
Ferreira M.M.C.
Institución
Resumen
Preferred signs of the dipole moment derivatives of the diacetylene have been determined by using G-sum rule graph and molecular orbital calculations. Atomic polar tensors and effective charges of the diacetylene are reported. The hydrogen effective charge calculated from the atomic polar tensor (ξH = 0.369e) is in excellent agreement with that obtained from aG-sum rule graph (ξH = 0.371e). MNDO calculations on the H(CC)nH(n = 1, 2, 3, 4 and 5) series indicate that the hydrogen effective charge increases with increasing number of CC units. This is due to the magnitude of the ∂pz/∂zH polar tensor element, as a consequence of the increasing charge flux along the series. Finally, this element seems to be a good indicator of the intrinsic acidity of acetylenic protons. © 1987. 43 3 345 348 Neto, Bruns, G sum rule applications for the vibrational intensities of the hydrocarbons (1979) The Journal of Chemical Physics, 71, p. 5042 Gussoni, Castiglioni, Zerbi, Charge distribution from infrared intensities: Charges on hydrogen atoms and hydrogen bond (1984) The Journal of Chemical Physics, 80, p. 1377 Kim, King, (1979) J. Molec. Struct., 57, p. 201 Koops, Visser, Smit, (1984) J. molec. Struct., 125, p. 179 Popov, Yakovlev, Lubuzh, Kogan, (1968) Zh. Perikl. Spektrosk., 8, p. 463 King, Mast, Blanchette, Infrared Intensity Sum Rule and Effective Charges (1972) The Journal of Chemical Physics, 56, p. 4440 Ramos, Neto, Bruns, (1980) J. phys. Chem., 84, p. 2808. , On the graphic representation of the G-sum rule, see for example Person, Newton, (1974) J. chem. Phys., 61, p. 1040 Dupuis, Rys, King, (1978) Quantum Chem. Program Exchange, , Program No. 403 Dewar, Thiel, (1977) J. Am. chem. Soc., 99, p. 4899 Dewar, Thiel, (1977) J. Am. chem. Soc., 99, p. 4907 Ramos, Neto, Bruns, Herrera, (1986) J. molec. Struct., 142, p. 209 Ramos, Neto, Bruns, Herrera, (1985) XVII European Congress on Molecular Spectroscopy, , Madrid (Spain) King, Mast, (1976) J. phys. Chem., 80, p. 2521 Person, Zilles, Rogers, Maia, (1982) J. molec. Struct., 80, p. 297 Eaborn, Skinner, Walton, (1966) J. Chem. Soc., B, p. 989 Eaborn, Skinner, Walton, (1966) J. Chem. Soc., B, p. 922 Chrisment, Delpnech, Thermodynamic and kinetic acidities in dimethyl sulphoxide. Part 2. Acetylenic compounds (1977) Journal of the Chemical Society, Perkin Transactions 2, 2, p. 407 Powell, Peterson, Csizmadia, (1983) J. molec. Struct., 92, p. 323