Hydrogen Bonding Interaction of Formic Acid‐, Formaldehyde‐, Formylfluoride‐Nitrosyl Hydride: Theoretical Study on the Geometries, Interaction Energies and Blue‐ or Red‐Shifted Hydrogen Bonds

Abstract

The hydrogen bonding interaction of formic acid-，formaldehyde-, formylfluoride-nitrosyl hydride complexes was investigated by the density functional theory (DFT) and ab inito method in conjunction with 6-311＋＋G(2d,2p) basis set. The geometries, vibrational frequencies and interaction energies of the complexes were calculated by both standard and CP-corrected methods respectively. Moreover, G3B3 method was employed to estimate the interaction energies. There are C-H…O, N-H…O, N-H…F blue-shifted H-bonds and red-shifted O-H…O H-bond in the complexes. Electron density redistribution and rehybridization contribute to the N-H and C-H blue shifts. All geometric reorganizations contribute to the N-H blue shifts and partial geometric reorganizations contribute to the C-H blue shifts. The geometric reorganizations of the complex C except ∠H(5)-O(4)-C(1) contribute to the O-H red shift. For the N-H blue shifts, the effect of r(N-O) variation on the N-H blue shifts is larger than that of ∠H-N-O variation. Rehybridization plays a dominant role in the degree of N-H blue shifts, whereas the electron density redistribution contributes more to the degree of C-H blue shifts than the other effects do.

Remarkable Blue Shifts of C−H and N−H Stretching Frequencies in the Interaction of Monosubstituted Formaldehyde and Thioformaldehyde with Nitrosyl Hydride

“…The magnitude of contraction and frequency blue shift of the C1−H2 bond in some complexes is close to, or somewhat larger than, the values reported in some previous literature. , Ying and co-workers predicted a contraction of the C−H bond length by 0.0010 Å in FCHO···HNO and 0.0034 Å in HCHO···HNO, leading to an increase in stretching frequency by 19 cm −1 for the former and 21 (symmetric mode) and 38 cm −1 (asymmetric mode) for the latter, calculated at the MP2/6-311++G(2d,2p) level of theory. Furthermore, Yang and co-workers reported a contraction of 0.0031 Å and a blue shift of 42 cm −1 for the C−H bond in CH 3 CHO···HNO computed at the MP2/6-311++G(d,p) level. The results obtained for structure G2 of CH 3 CHO···HNO in this work, which corresponds to the geometry mentioned in ref , amount to 0.004 Å and 53 cm −1 .…”

“…Furthermore, Yang and co-workers reported a contraction of 0.0031 Å and a blue shift of 42 cm −1 for the C−H bond in CH 3 CHO···HNO computed at the MP2/6-311++G(d,p) level. The results obtained for structure G2 of CH 3 CHO···HNO in this work, which corresponds to the geometry mentioned in ref , amount to 0.004 Å and 53 cm −1 .…”

“…Yang and co-workers showed a blue shift of both the C−H and N−H bonds in CH 3 CHO···HNO. Blue-shifted C−H bonds were also detected in the complexes between simple carbonyls such as HCHO, FCHO, and HNO, and between HCHO and HF. − Considering that a systematic examination of complexes formed from substituted carbonyls with nitrosyl hydride could shed light on the general behavior, we set out to theoretically consider in the present work the molecular interaction between XCHZ and HNO in which X = CH 3 , H, F, Cl, and Br, and Z = O and S, at a high level of theory. Our main goal is to obtain some features for a better understanding of the origin of the blue-shifting hydrogen bond, not only for the C−H bonds, but also for the N−H bonds in the types N−H···X, Z.…”

A computational study on multiple formaldehyde complexes and their possible chemical reactions as well as the catalytic effect in the gas phase

“…Our result show this unstability is 2.6 kcal/mol at the CCSD/6-311++g (3df, 3pd) level of theory. The mentioned researchers also calculated the trimer structures of formaldehyde, which were termed by EQ0 [3-0]-EQ9 [3][4][5][6][7][8][9] (see Figure 2 and Table 4 in reference [1]). The obtained energies at the B3LYP-D3/aug-cc-pVTZ level show that the EQ1 and EQ8 [3][4][5][6][7][8] were 0.19 and 11.16 kJ/mol more unstable than the EQ0 [3-0] structure [1].…”

“…Understanding and controlling intermolecular interactions play a crucial role in molecular recognition [1,2], crystal engineering [3][4][5][6] and biological systems [7,8]. Describing the interactions in molecular systems usually involves interpreting their geometry [9,10] and overall energy [11]. The nature of intramolecular cooperative effects between atoms of molecules helps us to understand the origin of molecular association.…”