PROIMI   05436
PLANTA PILOTO DE PROCESOS INDUSTRIALES MICROBIOLOGICOS
Unidad Ejecutora - UE
artículos
Título:
Density Functional Theory Calculations of the Molecular Force Field of L-Ascorbic Acid, Vitamin C
Autor/es:
BICHARA, L. C. BICHARA, LANÚS, H. E., NIETO, C. G., BRANDÁN, S. A.
Revista:
JOURNAL OF PHYSICAL CHEMISTRY A
Editorial:
AMER CHEMICAL SOC
Referencias:
Año: 2010 vol. 114 p. 4997 - 5004
ISSN:
1089-5639
Resumen:
We have studied L-ascorbic acid and characterized it by infrared spectroscopy in solid and aqueous solution
phases. The density functional theory (DFT) method together with Poples basis set show that three stable
molecules for the compound have been theoretically determined in the gas phase, and that an average of only
two more stable conformations are present in the solid phase, as it was experimentally observed. The harmonic
vibrational wavenumbers for the optimized geometries of both structures were calculated at B3LYP/6-31G*and
B3LYP/6-311++G** levels at the proximity of the isolated molecule. For a complete assignment of the
vibrational spectra in the compound solid and aqueous solution phases, DFT calculations were combined
with Pulays scaled quantum mechanics force field methodology in order to fit the theoretical wavenumber
values to the experimental ones. In this way, a complete assignment of all the observed bands in the infrared
spectrum for L-ascorbic acid was performed. The natural bond orbital study reveals the characteristics of the
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
vibrational spectra in the compound solid and aqueous solution phases, DFT calculations were combined
with Pulays scaled quantum mechanics force field methodology in order to fit the theoretical wavenumber
values to the experimental ones. In this way, a complete assignment of all the observed bands in the infrared
spectrum for L-ascorbic acid was performed. The natural bond orbital study reveals the characteristics of the
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
phases. The density functional theory (DFT) method together with Poples basis set show that three stable
molecules for the compound have been theoretically determined in the gas phase, and that an average of only
two more stable conformations are present in the solid phase, as it was experimentally observed. The harmonic
vibrational wavenumbers for the optimized geometries of both structures were calculated at B3LYP/6-31G*and
B3LYP/6-311++G** levels at the proximity of the isolated molecule. For a complete assignment of the
vibrational spectra in the compound solid and aqueous solution phases, DFT calculations were combined
with Pulays scaled quantum mechanics force field methodology in order to fit the theoretical wavenumber
values to the experimental ones. In this way, a complete assignment of all the observed bands in the infrared
spectrum for L-ascorbic acid was performed. The natural bond orbital study reveals the characteristics of the
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
vibrational spectra in the compound solid and aqueous solution phases, DFT calculations were combined
with Pulays scaled quantum mechanics force field methodology in order to fit the theoretical wavenumber
values to the experimental ones. In this way, a complete assignment of all the observed bands in the infrared
spectrum for L-ascorbic acid was performed. The natural bond orbital study reveals the characteristics of the
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
L-ascorbic acid and characterized it by infrared spectroscopy in solid and aqueous solution
phases. The density functional theory (DFT) method together with Poples basis set show that three stable
molecules for the compound have been theoretically determined in the gas phase, and that an average of only
two more stable conformations are present in the solid phase, as it was experimentally observed. The harmonic
vibrational wavenumbers for the optimized geometries of both structures were calculated at B3LYP/6-31G*and
B3LYP/6-311++G** levels at the proximity of the isolated molecule. For a complete assignment of the
vibrational spectra in the compound solid and aqueous solution phases, DFT calculations were combined
with Pulays scaled quantum mechanics force field methodology in order to fit the theoretical wavenumber
values to the experimental ones. In this way, a complete assignment of all the observed bands in the infrared
spectrum for L-ascorbic acid was performed. The natural bond orbital study reveals the characteristics of the
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
vibrational spectra in the compound solid and aqueous solution phases, DFT calculations were combined
with Pulays scaled quantum mechanics force field methodology in order to fit the theoretical wavenumber
values to the experimental ones. In this way, a complete assignment of all the observed bands in the infrared
spectrum for L-ascorbic acid was performed. The natural bond orbital study reveals the characteristics of the
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
++G** levels at the proximity of the isolated molecule. For a complete assignment of the
vibrational spectra in the compound solid and aqueous solution phases, DFT calculations were combined
with Pulays scaled quantum mechanics force field methodology in order to fit the theoretical wavenumber
values to the experimental ones. In this way, a complete assignment of all the observed bands in the infrared
spectrum for L-ascorbic acid was performed. The natural bond orbital study reveals the characteristics of the
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.
L-ascorbic acid was performed. The natural bond orbital study reveals the characteristics of the
electronic delocalization of the three structures while the corresponding topological properties of electronic
charge density are analyzed by employing Baders atoms-in-molecules theory.