Water-Mediated Electronic Structure of Oligopeptides Probed by Their UV Circular Dichroism, Absorption Spectra, and Time-Dependent DFT Calculations

TD-DFT Calculations, Electronic Structure, Biological Activity, NBO, NLO Analysis and Electronic Absorption Spectra of Some 3-Formylchromone Derivatives

The electronic structure and spectra of 3-formylchromone and some of its derivatives are investigated using TD-DFT/B3LYB/6-311G (d, p) level of theory. The results of calculations show that all the studied compounds 1–6 are planar, as indicated from the dihedral angles. The electronic absorption spectra of the studied compounds are recorded in the UV-Vis region, in both ethanol (as polar solven...

Predicting near-UV electronic circular dichroism in nucleosomal DNA by means of DFT response theory.

It is demonstrated that time-dependent density functional theory (DFT) calculations can accurately predict changes in near-UV electronic circular dichroism (ECD) spectra of DNA as the structure is altered from the linear (free) B-DNA form to the supercoiled N-DNA form found in nucleosome core particles. At the DFT/B3LYP level of theory, the ECD signal response is reduced by a factor of 6.7 in g...

In vitro study of drug-protein interaction using electronic absorption, fluorescence, and circular dichroism spectroscopy

In the near future, design of a new generation of drugs targeting proteins will be required. Considering the complex bond between the drug and protein, the structure and stability of the target protein should be considered. So far, a series of in vitro investigations have been conducted with the aim of predicting drug-biological medium interactions. In these studies, use of spectroscopic method...

Time-dependent DFT simulation of UV- spectra and molecular structure of several bis-pyrazolopyridines derivatives

Transfer of Frequency-Dependent Polarizabilities: A Tool To Simulate Absorption and Circular Dichroism Molecular Spectra.

Absorption and circular dichroism spectra reveal important information about molecular geometry and electronic structure. For large molecules, however, spectral shapes cannot be computed directly. In the past, transition dipole coupling (TDC) and related theories were proposed as simplified ways of calculating the spectral responses of large systems. In the present study, an alternative approac...