Theoretical Investigations on the π-π Stacking Interactions in Phenol-Water Complexes

Abstract

Non covalent interactions are quite common in all kinds of π-systems, such as π-π interactions, long range/short range van der waal force of interactions, ion-π interactions etc. Ab initio calculations are well established and account well for the experimental long range interaction energies for small clusters of aromatic molecules and most of the calculations were carried out using the MPn methods. If a reasonably large basis set is used to calculate the stacking interaction energies for a cluster (dimer, trimer etc.) of aromatic molecules then the electron-electron correlation energy may be properly calculated.Moreover, ab initio calculations for aromatic π-systems show that the calculated stacking interaction energies highly depend on the basis set used and the electron correlation energy. In this investigation, the electron correlation of the stacked hydrated phenol systems has been accounted at MP2 level of calculations. We have calculated the π-π stacking interaction energies of the hydrated phenolic systems with different conformations.

Effective Removal of Water-Soluble Methylated Arsenic Contaminants with Phosphorene Oxide Nanoflakes: A DFT Study

“…In terms of toxicity, trivalent arsenicals are more toxic and mobile than pentavalent ones, which is related to the speciation and its affinity with the -SH groups in biomolecules such as glutathione and cysteinyl residues in enzymes [55][56][57]. In the first place, trivalent arsenicals are deprotonated above pH=9.2; then, trivalent arsenicals are neutrally charged at neutral and physiological pH [55,58].…”

Molecular structure and conformational properties of triflamide derivatives in the gas phase—Part II: 6‐Iodo‐3‐(triflamidomethyl)‐4‐triflyl‐1,4,2,7‐oxaazadisilepane and 2,2,4,4‐tetramethyl‐6,8‐bis (triflyl)‐3‐oxa‐6,8‐diaza‐2,4‐disilabicyclo[3.2.2]nonane by gas‐phase electron diffraction and theoretical calculations

“…Conformational diversity in the gas phase may in some cases be much more pronounced than in solution or crystal. [4][5][6][7] Recently, we have shown that the iodotriflamidation at the two C=C bonds in 1,1,3,3-tetramethyl-1,3-divinyldisiloxane affords two new heterocycles, 6-iodo-3-(triflamidomethyl)-4-triflyl-1,-4,2,7-oxazadisilepane 1 and 2,2,4,4-tetramethyl-6,8-bis (triflyl)-3-oxa-6,8-diaza-2,4-disilabicyclo[3.2.2]nonane 2 via the intermediate N,N'-(1,1,3,3-tetramethyldisiloxane-1,3-diyl)bis(2-iodoethane-2,1-diyl)bistriflamide undergoing two successive dehydroiodination reactions to give compounds 1 and 2, respectively. 8 The structure of both compounds was proved by single crystal X-ray diffraction.…”

“…Moreover, due to a very short time of interaction of the diffracting electron with a single molecule, ~10 −18 s, the GED method is able to provide information on rather fast conformational transitions, as compared with the NMR method. Conformational diversity in the gas phase may in some cases be much more pronounced than in solution or crystal 4–7 …”

Removal of Water-Soluble Inorganic Arsenicals with Phosphorene Oxide Nanoadsorbents: A First-Principles Study

“…Arsenicals are highly toxic compounds whose chronic exposure has been associated with carcinogenic, endocrine, cardiovascular diseases, skin and lung damage, diabetes, and metabolic syndrome [1][2][3][4]. The arsenic toxicity is related to its ability to replace phosphate groups in biomolecules, showing a strong affinity with −SH groups of cysteinyl residues [5,6].…”