On the Ag+–cytosine interaction: the effect of microhydration probed by IR optical spectroscopy and density functional theory

2015 ◽  
Vol 17 (39) ◽  
pp. 25915-25924 ◽  
Author(s):  
Matias Berdakin ◽  
Vincent Steinmetz ◽  
Philippe Maitre ◽  
Gustavo A. Pino
Keyword(s):  
Density Functional Theory ◽  
Water Molecule ◽  
Optical Spectroscopy ◽  
Density Functional ◽  
Functional Theory ◽  
Single Water Molecule

Single water molecule hydration stabilizes two quasi-isoenergetic complexes of cytosine⋯Ag+.

Influence of water on the CH3O˙ + O2 → CH2O + HO2˙ reaction

2019 ◽  
Vol 21 (28) ◽  
pp. 15734-15741 ◽  
Author(s):  
Subhasish Mallick ◽  
Amit Kumar ◽  
Brijesh Kumar Mishra ◽  
Pradeep Kumar
Keyword(s):  
Density Functional Theory ◽  
Electronic Structure ◽  
Water Molecule ◽  
Density Functional ◽  
Electronic Structure Calculations ◽  
Functional Theory ◽  
Influence Of Water ◽  
Single Water Molecule ◽  
Structure Calculations

Electronic structure calculations employing density functional theory have been used to study the effect of a single water molecule on the CH3O˙ + O2 → CH2O + HO2˙ reaction.

Application of Time-Dependent Density Functional Theory and Optical Spectroscopy toward the Rational Design of Novel 3,4,5-Triaryl-1-R-1,2-diphospholes

2013 ◽  
Vol 117 (31) ◽  
pp. 6827-6834 ◽  
Author(s):  
Elena E. Zvereva ◽  
Stefan Grimme ◽  
Sergey A. Katsyuba ◽  
Timur I. Burganov ◽  
Almaz A. Zagidullin ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Optical Spectroscopy ◽  
Density Functional ◽  
Rational Design ◽  
Time Dependent ◽  
Functional Theory ◽  
Dependent Density

Application of density functional theory and optical spectroscopy for the prediction of the photophysical properties of Р-pyridylphospholanes

2019 ◽  
Vol 68 (2) ◽  
pp. 254-261 ◽  
Author(s):  
T. P. Gerasimova ◽  
A. V. Shamsieva ◽  
I. D. Strelnik ◽  
S. A. Katsyuba ◽  
E. I. Musina ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Optical Spectroscopy ◽  
Density Functional ◽  
Photophysical Properties ◽  
Functional Theory

scholarly journals Density functional theory meta GGA study of water adsorption in MIL-53(Cr)

2019 ◽  
Vol 34 (3) ◽  
pp. 227-232 ◽  
Author(s):  
E. Cockayne
Keyword(s):  
Density Functional Theory ◽  
Water Molecule ◽  
Density Functional ◽  
Critical Concentration ◽  
Metal Organic Framework ◽  
Water Dimer ◽  
Hydroxyl Group ◽  
Water Molecules ◽  
Generalized Gradient ◽  
Functional Theory

We use density functional theory meta-generalized gradient approximation TPSS + D3(BJ) + U + J calculations to investigate the energetics and geometry of water molecules in the flexible metal-organic framework material Materials of Institut Lavoisier (MIL)-53(Cr) as a function of cell volume. The critical concentration of water to cause the transition from the large pore (lp) to the narrow pore (np) structure is estimated to be about 0.13 water molecule per Cr. At a concentration x = 1 water molecule per Cr, the zero-temperature np and lp configurations each have a hydrogen bond between the H of each framework hydroxyl group and water oxygen (OW). At intermediate volumes, water dimer-like configurations are observed. A concentration x = 1.25 leads to hydrogen bonding between water molecules in the np phase that is absent for x = 1. Our results suggest possible mechanisms for pore closing in hydrated MIL-53(Cr).

scholarly journals Influence of water on the surface of graphene

2018 ◽  
Vol 174 ◽  
pp. 06002
Author(s):  
Yunus Kaya ◽  
Yalçin Kalkan ◽  
Rob Veenhof
Keyword(s):  
Density Functional Theory ◽  
Water Molecule ◽  
Density Functional ◽  
Theoretical Models ◽  
Surface Conductivity ◽  
Basis Set ◽  
Hybrid Functional ◽  
Functional Theory ◽  
The Density Functional Theory ◽  
Influence Of Water

We have studied how water modifies the surface of graphene and in particular how the surface conductivity of graphene is affected. According to the literature, two types of interactions should be distinguished: physical, where a water molecule remains intact and is located at some distance from the mesh, and chemical, where a water molecule is imbricated in the graphene bond structure. We have developed theoretical models for both types of interactions using the density functional theory (DFT) with the B3LYP hybrid functional combined with the 6-31G(d) basis set. Our calculations show that the surface conductivity of graphene is reduced in the presence of water.

scholarly journals Synthesis, Experimental and Density Functional Theory (DFT) Studies on Solubility of Camptothecin Derivatives

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3170 ◽  
Author(s):  
Chin-Hung Lai ◽  
Chia-Chin Chang ◽  
Yi-Lin Weng ◽  
Ta-Hsien Chuang
Keyword(s):  
Density Functional Theory ◽  
Water Molecule ◽  
Dimethyl Sulfoxide ◽  
Normal Saline ◽  
Density Functional ◽  
Solvent System ◽  
Aprotic Solvents ◽  
Dft Studies ◽  
Functional Theory ◽  
Solvent Systems

Two camptothecin derivatives, 10-cyclohexyl-7-methyl-20(S)-camptothecin and 7-methyl-10-morpholino-20(S)-camptothecin, were synthesized and their differences in solubility were investigated using four chosen solvent systems. Based on our results, 10-cyclohexyl-7-methyl-20(S)-camptothecin exhibited higher solubilities than 7-methyl-10-morpholino-20(S)-camptothecin in polar aprotic solvents. However, these two camptothecin derivatives did not exhibit apparent differences in solubility between 5% dimethyl sulfoxide (DMSO)/95% normal saline co-solvent system and 5% dimethylacetamide (DMAC)/95% normal saline co-solvent system. To rationalize their differences in solubility, we also tried to perform a DFT-B3LYP study to investigate their interaction with one water molecule.

scholarly journals Revisiting the reactivity between HCO and CH3 on interstellar grain surfaces

2020 ◽  
Vol 493 (2) ◽  
pp. 2523-2527 ◽  
Author(s):  
J Enrique-Romero ◽  
S Álvarez-Barcia ◽  
F J Kolb ◽  
A Rimola ◽  
C Ceccarelli ◽  
...  
Keyword(s):  
Water Molecule ◽  
Energy Barrier ◽  
Density Functional ◽  
High Energy ◽  
Functional Theory ◽  
Radical Coupling ◽  
High Energy Barrier ◽  
Single Water Molecule ◽  
Complex Organic

ABSTRACT The formation of interstellar complex organic molecules is currently thought to be dominated by the barrierless coupling between radicals on the interstellar icy grain surfaces. Previous standard density functional theory (DFT) results on the reactivity between CH3 and HCO on amorphous water surfaces showed that the formation of CH4 + CO by H transfer from HCO to CH3 assisted by water molecules of the ice was the dominant channel. However, the adopted description of the electronic structure of the biradical (i.e. CH3/HCO) system was inadequate [without the broken-symmetry (BS) approach]. In this work, we revisit the original results by means of BS-DFT both in gas phase and with one water molecule simulating the role of the ice. Results indicate that the adoption of BS-DFT is mandatory to describe properly biradical systems. In the presence of the single water molecule, the water-assisted H transfer exhibits a high energy barrier. In contrast, CH3CHO formation is found to be barrierless. However, direct H transfer from HCO to CH3 to give CO and CH4 presents a very low energy barrier, hence being a potential competitive channel to the radical coupling and indicating, moreover, that the physical insights of the original work remain valid.

Sign in / Sign up

Export Citation Format

Share Document