Linear and Cyclic Clusters of Hydrogen Cyanide and Cyanoacetylene:  A Comparative ab Initio and Density Functional Study on Cooperative Hydrogen Bonding

Abstract

The equilibrium structures, the stabilization energies, the harmonic vibrational spectra, and the infrared intensities of linear and cyclic hydrogen cyanide, (HCN) n , and cyanoacetylene oligomers, (HC3N) n , were calculated at the ab initio self-consistent field and at the Møller−Plesset second-order level, as well as with the aid of a density functional method. Several extended basis sets were applied. The systematic modifications of the most important properties characteristic for the C−H- - -N hydrogen bond in these two series of intermolecular clusters, in particular, the intermolecular distances, R(H- -N), the intramolecular distances, R(C−H), the interaction energies per hydrogen bond, with and without zero-point energy corrections, the C−H stretching frequencies, ν(C−H), and their corresponding infrared intensities were monitored as a function of the oligomer size and are discussed in detail. The mode of convergence to the infinite chain limit is described and found to be qualitatively quite similar in both systems. From a quantitative point of view, all features usually attributed to hydrogen-bond nonadditivity are somewhat weaker for the cyanoacetylene clusters, mainly a consequence of the molecular size. Tentative assignments are suggested for the infrared active vibrations of larger cyclic cyanoacetylene clusters.

Theoretical Study of the Interplay between Lithium Bond and Hydrogen Bond in Complexes Involved with HLi and HCN

“…[15] It is also observed from the table that the SCF binding distance is smaller than the corresponding MP2 result, which is inconsistent with that found for N···HC hydrogen bond in HCN dimer. [39] With the 6-311 + + G(d,p) basis set, the binding energy at the MP2 level is almost close to that at the QCISD level and the binding energy at the MP4(SDQ) level equals to that at the QCISD level, indicating a negligible effect of higher-order excitation. This is consistent with that in HCNÀHCN complex.…”

Cooperative Effect of Hydrogen-Bonded Chains in the Environment of a π → π* Chromophore

“…[2][3][4][5][6][7] These effects are fully corroborated by quantum mechanical calculations of linear chains of simple hydrogen-bonded molecules such as HCN, HF, and cyanoacetylene as well as water clusters. [8][9][10][11][12][13] Chains or wires of hydrogen-bonded H 2 O and NH 3 molecules have been the objects of our research 15,16 due to their possible role in the excited-state hydrogen atom-transfer processes in biological systems.…”

Interplay between tetrel bonding and hydrogen bonding interactions in complexes involving F2XO (X=C and Si) and HCN

“…The orbital interactions and natural population analysis (NPA) charges were calculated with natural bond orbital (NBO) theory [39] using NBO version 3.1 implemented in Gaussian 09. To gain an insight into the nature of the investigated intermolecular interactions, the energy decomposition analysis (EDA) was performed by the GAMESS program [40] with the localized molecular orbital EDA method 6 [41] at the MP2/aug-cc-pVTZ level.…”

“…Hydrogen cyanide (HCN) is a common interstellar molecule [1], produced in the reactions of ammonia and methane [2], and is also of great importance in atmospheric chemistry as a result of its release by biomass burning [3], thus the structures and the vibrational spectra of small, hydrogen-bonded clusters of HCN in the gas phase have been the subject of extensive investigations, both experimentally and theoretically [4][5][6]. The polymers of HCN turned out to be of particular interest [6][7][8][9][10][11][12] due to the existence of cooperativity in these clusters, which has a significant contribution to the applications of hydrogen bonds in catalytic reactions, molecular materials, molecular recognition, and biological systems.…”

“…The polymers of HCN turned out to be of particular interest [6][7][8][9][10][11][12] due to the existence of cooperativity in these clusters, which has a significant contribution to the applications of hydrogen bonds in catalytic reactions, molecular materials, molecular recognition, and biological systems. It has proved that the HCN polymer in the gas phase exists in both a linear and a cyclic form [11] but in the solid state arranges in extended, perfectly linear chains [12].…”