Triaziridine and tetrazetidine vs. cyclic water trimer and tetramer: A computational approach to the relationship between molecular and supramolecular conformational analysis

Abstract

The potential energy surfaces of cyclic water trimer and tetramer, as typical examples of supramolecular systems, have been compared with those of triaziridine and tetrazetidine, which can be considered as their suitable molecular analogues. The survey was performed at the B3LYP/6-311+G(3df,2p)//B3LYP/6-31+G(d,p) level of theory and includes also the monomethyl and monofluoro derivatives of both the trimer and the tetramer. This comparison leads to the conclusion that supramolecular systems, where the molecular components are held together by weak interactions, exhibit the same conformational features as the analogous molecular compounds, where the constituent atoms are held together by strong covalent bonds. More importantly, even though in the former the energy required to induce conformational rearrangements is much smaller than that needed for typical molecular systems, there is a fairly good linear relationship between both magnitudes. We have also found that this quantitative relationship can be perturbed when the through-space interactions, either repulsive or attractive, between the substituents are sufficiently strong.

Stability of cyclic (H2O)n clusters within molecular solids: Role of aromaticity

“…For comparison, we optimized the structure of the lowest nuclearity cyclic water cluster, a trimer (H 2 O) 3 as a cyclic (H 2 O) 3 is unavailable in the database. Consistent with previous reports, the (H 2 O) 3 structure has a udu orientation of the hydrogen positions along the trimeric H‐bonded triangle 24.…”

Cooperative Effects and Strengths of Hydrogen Bonds in Open-Chaincis-Triaziridine Clusters (n= 2−8): A DFT Investigation

“…The triaziridine molecule and its isomers have been extensively studied mainly on the electron energies, thermochemical properties, conformational analyses, and the ring strains of isolated molecules by using ab initio methods. 1,[3][4][5][6][7][8][9][10] These studies indicated that the triaziridine system is stable enough to be isolated.…”

“…Triaziridine was synthesized first in the form of silver complex early in 1977 and has not been isolated experimentally as a free molecule so far. The triaziridine molecule and its isomers have been extensively studied mainly on the electron energies, thermochemical properties, conformational analyses, and the ring strains of isolated molecules by using ab initio methods. ,− These studies indicated that the triaziridine system is stable enough to be isolated.…”

Assessing Intermolecular Interactions in Guest-Free Clathrate Hydrate Systems

“…Thus, a significant amount of work has been already directed toward validating the performance of the DFT-D3 method, which it has been found to be reliable for describing noncovalent interactions. [31][32][33] Numerous ab initio studies have investigated the binding energies of various water clusters, 12,19,20,[34][35][36] ranking the accuracy of DFT functionals, however they have focused primarily on small water clusters, rarely containing more than eight water molecules, 11 and just recently new reference data for the interactions energies of water icosamers have been reported. 16,19,21,35 Given the recent interest in such complexes, and the lack of reference computations motivates us to assess available force fields, and common as well as improved DFT approaches for representing the interactions of such systems with strong cooperative many body effects.…”