Kinds Of Hydrogen Bonds Research Articles

Engineering network entanglement of functionalized graphene oxide/poly(acrylamide) nanocomposites for enhanced oil recovery

Hydroxyl-functionalized graphene oxide (OGO) was prepared from graphene oxide (GO) modified by diethanolamine (DEOA) to promote the interaction between nano sheets and polymer molecules. Three OGO samples with different GO to DEOA ratios, and an acrylamide-based polymer (PM) were synthesized. The nanoparticle and polymer hybrid systems were prepared using GO or OGO suspension into PM solution. The interaction strength investigation indicated that the hybrid system had two kinds of hydrogen bonds, one is between amide groups on polymer and the other is between amide groups on polymer and hydroxyl groups on nanosheets, and there was a competition for them. As a result, a proper surface hydroxyl density is critical to form a suitable molecular network for improving the hybrid property under harsh condition. The rheological properties of PM solution and these hybrid systems were studied, and the results showed that the introduction of OGO obviously improved the salt-resistance and temperature-tolerance of PM solution. The results from oil displacement experiments showed that the enhanced oil recovery ratio jumped to 20.9% for PM/OGO system, while it was only 13.8% for PM solution.

New insights into the excited state intramolecular proton transfer (ESIPT) competition mechanism for different intramolecular hydrogen bonds of Kaempferol and Quercetin in solution

In this work, the process of the Excited State Intramolecular Proton Transfer (ESIPT) competition of Kaempferol and Quercetin in methanol was studied by means of the Density Functional Theory (DFT) and the Time-Dependent Density Functional Theory (TDDFT) method. Two different ESIPT reaction pathways were analyzed by the variation trend of the 3D potential energy surfaces (PESs) with the change of the intramolecular hydroxyl bond length through the PESs of the two molecules of the ground state (S0) and the first excited (S1) state. The ESIPT process only occurred between O25–H28 and O22–H28 and was completed within 33.1fs by molecular excited state dynamics simulation. It is demonstrated that when there are two kinds of hydrogen bonds in the molecule, the ESIPT prefers the six-membered ring hydrogen bonds to the five-membered ring hydrogen bonds.

A Solid Transformation into Carboxyl Dimers Based on a Robust Hydrogen-Bonded Organic Framework for Propyne/Propylene Separation.

Self-assembly of N,N,N',N'-tetrakis(4-carboxyphenyl)-1,4-phenylenediamine with the help of different solvents provides isostructural hydrogen-bonded organic frameworks (HOF-30). Single-crystal X-ray diffraction (SCXRD) analysis reveals HOF-30 possesses 3D ten-fold interpenetrated dia nets connected by two kinds of hydrogen bonds, namely solvent-bridged carboxyl dimers and carboxyl⋅⋅⋅carboxyl dimers. Degassing treatment for HOF-30 yields HOF-30a with 3D ten-fold interpenetrated dia nets but linked with sole carboxyl⋅⋅⋅carboxyl dimers. Reversible hydrogen-bond-to-hydrogen-bond transformation between solvent-bridged carboxyl dimers in HOF-30 and carboxyl⋅⋅⋅carboxyl dimers in HOF-30a has been unveiled by single-crystal and powder X-ray diffraction. In addition, HOF-30a enables the selective adsorption of propyne over propylene according to single-component sorption and breakthrough experiments. The preferred propyne location in HOF has also been identified by SCXRD test.

A Solid Transformation into Carboxyl Dimers Based on a Robust Hydrogen‐Bonded Organic Framework for Propyne/Propylene Separation

AbstractSelf‐assembly of N,N,N′,N′‐tetrakis(4‐carboxyphenyl)‐1,4‐phenylenediamine with the help of different solvents provides isostructural hydrogen‐bonded organic frameworks (HOF‐30). Single‐crystal X‐ray diffraction (SCXRD) analysis reveals HOF‐30 possesses 3D ten‐fold interpenetrated dia nets connected by two kinds of hydrogen bonds, namely solvent‐bridged carboxyl dimers and carboxyl⋅⋅⋅carboxyl dimers. Degassing treatment for HOF‐30 yields HOF‐30a with 3D ten‐fold interpenetrated dia nets but linked with sole carboxyl⋅⋅⋅carboxyl dimers. Reversible hydrogen‐bond‐to‐hydrogen‐bond transformation between solvent‐bridged carboxyl dimers in HOF‐30 and carboxyl⋅⋅⋅carboxyl dimers in HOF‐30a has been unveiled by single‐crystal and powder X‐ray diffraction. In addition, HOF‐30a enables the selective adsorption of propyne over propylene according to single‐component sorption and breakthrough experiments. The preferred propyne location in HOF has also been identified by SCXRD test.

Molecular dynamics study on ultra-confined NaCl solution in the silane coupling agent modified rubber calcium silicate hydrate nano-pore

The corrosive ions in the coastal environment invade the rubber concrete structure through capillary adsorption, which greatly limits the reuse of waste rubber. Silane coupling agent (SCA) modified rubber concrete gradually enters people's field of vision due to the improvement of its mechanical properties, and at the same time, it helps to improve the durability of the material. However, the interaction mechanism of action of ions with SCA and rubber is still unclear. Based on molecular dynamics theory, this study simulates the NaCl solution in the pores of C-S-H gel and rubber before and after SCA modification. Through the analysis of the local structure and dynamic performance of water molecules and ions, it is found that the direction of the distribution of water molecules at the rubber interface is opposite to that of C-S-H. The order of water molecules on the silane interface is enhanced, and it has a richer hydrogen bond network. The hydrophobicity of rubber has been confirmed on a microscopic scale, while silane has a duality to water molecules. The silanol group close to the C-S-H substrate is hydrophilic and can form hydrogen bonds with water molecules, while the tail alkane group is highly hydrophobic. Moreover, rubber and silane are not conducive to the adsorption of Na+ and Cl- and will change the coordination of ions at the interface. Although there are many kinds of hydrogen bonds between silane and water molecules, the stability is poor. The addition of silane will slow down the movement speed of water molecules in the pores, thereby indirectly improving the resistance of the SCA modified rubber cement-based material to corrosion by chloride ions.

Conformer selective monohydrated clusters of 1,2,3,4 –tetrahydroisoquinoline in S0: I-Potential energy surface studies, vibrational signatures and NBO analysis

The global minima in the potential energy surface of 1, 2, 3, 4-tetrahydroisoquinoline (THIQ):(H2O) prefer the twisted equatorial orientation of the NH group. It is characterized by a strong OH⋅⋅⋅N and a weak O-H⋅⋅⋅π hydrogen bonds. The computations at the ab initio level and DFT methods with M06–2X and ωB97X-D functionals generated consistent results. The monohydrate with the axial orientation of NH having a single OH⋅⋅⋅N bond in the twisted configuration of THIQ is higher by 240 ± 40 cm−1. The N⋅⋅⋅H bond length is smaller in the latter. All the clusters are located in the potential energy surface of THIQ :(H2O) drawn with the variation of the dihedral angles of the saturated ring of THIQ. Various kinds of hydrogen bonds are observed. Binding energy of each structure is computed incorporating BSSE corrections. Interestingly, the largest of them correspond to a conformer of THIQ, where it was a transition state in the bare molecule. The vibrational analysis of the clusters indicates the reassignment of a number of bands in the observed IR spectra. The red-shifts observed in the different stretching modes of water in the two lowest energy clusters are suitably explained. This is further verified from NBO computations. The changes in s-character, NBO energies and OH bond lengths with the variation of hydrogen bond distances clearly signify the dominant nature of hyperconjugation mechanism. The natures of each OH bonds of water are investigated thoroughly. The bond which is not taking part in hydrogen bonding shows some apparently unexpected behaviors. HOMO and LUMO plots and their energy differences are employed to qualitatively explain the experimental results observed earlier. Changes in Molecular Electrostatic Potentials (MEP) on cluster formation are explained and confirm our computations. Maximum hardness principle (MHP) is followed by the most stable monohydrate only. Hardness values display a certain arrangement depending on the type of hydrogen bonding sites. We suggest further experiments to confirm our key observations.

D-Retro Inverso Amylin and the Stability of Amylin Fibrils.

Motivated by the role that amylin aggregates play in type-II diabetes, we compare the stability of regular amylin fibrils with the stability of fibrils where l-amino acid chains are replaced by d-retro inverso (DRI) amylin, that is, peptides where the sequence of amino acids is reversed, and at the same time, the l-amino acids are replaced by their mirror images. Our molecular dynamics simulations show that despite leading to only a marginal difference in the fibril structure and stability, aggregating DRI-amylin peptides have different patterns of contacts and hydrogen bonding. Because of these differences, DRI-amylin, when interacting with regular (l) amylin, alters the elongation process and lowers the stability of hybrid amylin fibrils. Our results not only suggest the potential use of DRI-amylin as an inhibitor of amylin fibril formation but also point to the possibility of using the insertion of DRI proteins in l-assemblies as a way to probe the role of certain kinds of hydrogen bonds in supramolecular assemblies or aggregates.

Exploration of H2S capture by alkanolamines

H2S is a kind of impurity in the alternative energy resource of biogas and landfill gas. Among the removal methods, absorption by alkanolamines is the commonly accepted and widely used ones. This is due to the efficient regeneration. In this study, the absorption mechanism of H2S by two alkanolamines, namely diethanolamine (DEA) and N-methyldiethanolamine (MDEA), was proposed in a different way and analyzed by DFT calculations. The structural, energetic, red shifts and topological analysis of the most stable structures were then investigated. The values of electron densities and Laplacian densities at the bond critical points fall in the range of a hydrogen bond. Two kinds of hydrogen bonds S–H···N and O–H···S formed between H2S and DEA/MDEA are considered to be the driving forces during the absorption process. Thus, it can be known that H2S can act as both a hydrogen bond acceptor and a donor. Besides, the S–H···N hydrogen bond is much stronger than the O–H···S hydrogen bond. According to the change rules of Gibbs energies, the formation of hydrogen bond becomes difficult with increasing temperature and deceasing pressure. The absorption mechanism of H2S captured by alkanolamines via hydrogen bond interaction provides a novel theoretical direction for further study.

Heterogeneous Occupancy and Vibrational Dynamics of Spatially Patterned Water Molecules.

We performed first-principles molecular dynamics simulations of relatively dilute aqueous solutions of sulfate and thiosulfate dianions to analyze the structure, dynamics, and vibrational spectral properties of water molecules around the solute, especially the spatially patterned solvent molecules in the first solvation layer and the extended layers. This study also involves the investigation of dynamics of dangling OH groups in these layers and their role in patterning the water molecules around the dianions. Structural evaluation of the systems is carried out by radial distribution functions, number integrals, and spatial distribution functions. The lifetime of dangling OH groups inside the solvation shell is compared more to that of the bulk. By constructing the O-H groups in three ensembles (S1, S2, and S3) around the anion, we show that the frequency distribution of OH modes in the S1 ensemble show red-shifting for both sulfate and thiosulfate. The O-H groups in the S2 ensemble of the sulfate-water system show red-shifting by 10 cm-1, while in the case of thiosulfate-water, these O-H groups show blue-shifting by 8 cm-1. The water molecules in S1 and S2 subensembles have slower dynamics compared to those in the bulk (S3). The dynamics of various kinds of hydrogen bonds were characterized by hydrogen bond population correlation functions. The spectral diffusion of solvation shell O-H modes was performed through a frequency-time correlation function. We find a significant amount of orientational retardation of water molecules in the S1 layer and moderate retardation in the S2 layer as compared to that in the bulk, S3 layer. All these findings, the red shift of the OH stretching frequency in S1 and S2 layers, slowing down of the orientational dynamics of OH vectors in S1 and S2 layers, and less diffusivity of water in S1 and S2 layers, show the long-range kosmotropic effect of multivalent sulfate and thiosulfate oxyanions. Due to the long-range effect, heterogeneous occupancy of water molecules is observed, and the water molecules are found to arrange in a patterned manner in the vicinity of anions with varied local density.

Structural Transformation and Dyeing Performance of Poly(Ethylene Terephthalate) Filament Using Dicationic Imidazolium Ionic Liquid

3,3'-[1,2-ethanediylbis (oxy-2,1-ethanediyl)]-bis[1-methyl-imidazolium]-dibromide (DImDBr), a gemini imidazolium ionic liquid, was synthesized for the modification and dyeing promotion of poly(ethylene terephthalate) (PET) filaments. The results showed that parameters such as treatment temperature, time, and DImDBr concentration played a critical role on the tensile strength and tensile strength retention of modified PET filaments. The optimal treatment parameters of the PET filaments were 120 °C for 90 min with addition of 6 % ionic liquid. The influence of disperse dyeing parameters (temperature, time, and dye concentration) on DImDBr modified PET filaments were also studied. The disperse dyed PET filaments (after treatment with DImDBr) exhibited a desirable color strength (K/S value), excellent soap washing fastness, light fastness, and rubbing fastness. Furthermore, the native PET filaments and DImDBr treated PET filaments were characterized by FT-IR, XRD, DSC, TGA, and SEM. Density functional theory (DFT) simulation showed the presence of two kinds of hydrogen bonds (C-H/O and O-H/Br) and eight strong hydrogen bonds in the DImDBr/cis-PET monomers, while only three hydrogen bonds were found in the DImDBr/trans-PET monomers. The structural transformation from the crystalline phase to the amorphous phase (FT-IR, XRD, and DFT simulation) after DImDBr modification confirmed the dyeing promotion of PET filaments at lower temperature.

Effect of cationic structure of ionic liquids on dissolution and regeneration of white hide powder

3-methyl-1-ethoxycarbonylimidazolium chloride ([EtMIM]Cl), was synthesized for white hide powder dissolution. White hide powder was successfully dissolved in [EtMIM]Cl, and regenerated from methanol. The dissolution data and thermodynamic parameter of white hide powder in [EtMIM]Cl and [BMIM]Cl were studied. Hydrogen bond basicity (β) and general polarizability (π*) of ILs were determined. The white hide powders were characterized by FT-IR, XRD, and TGA. The results showed that the maximum solubility of white hide powder in [EtMIM]Cl was higher than that in [BMIM]Cl at same dissolution temperature. At same temperature and same solid content, the dissolution time of white hide powder in [EtMIM]Cl was shorter than that in [BMIM]Cl. Density functional theory (DFT) simulation showed that two kinds of hydrogen bonds (C-H/O and C-H/Cl) and eight strong hydrogen bonds are found in [EtMIM]Cl/GPH, while seven hydrogen bonds are found in [BMIM]Cl/GPH. The carboxylic acid ester cationic group in [EtMIM]+ has more electronegative ester groups and stronger electronic cloud density oxygen atoms than alkyl group in [BMIM]+, [EtMIM]Cl is easier to destroy the intermolecular or intramolecular hydrogen bonds in white hide powder, so as to accelerate the dissolution of white hide powder in [EtMIM]Cl. The molecular simulation results indicated that both Cl− anions and [EtMIM]+ cation played important roles in the white hide powder dissolution.

Dissolution and regeneration behavior of chitosan in 3-methyl-1-(ethylacetyl)imidazolium chloride

3-methyl-1-(ethylacetyl)imidazolium chloride ([EtMIM]Cl), was synthesized for chitosan dissolution, and the dissolution and regeneration behaviors of chitosan in [EtMIM]Cl were thoroughly investigated. The solubility of chitosan in [EtMIM]Cl was measured at temperatures ranging from 40 °C to 110 °C, based on which the thermodynamic parameters of chitosan in [EtMIM]Cl were calculated. The polarizability and hydrogen bond accepting ability was determined by solvatochromic UV/vis spectroscopy. The regenerated chitosan from [EtMIM]Cl by adding methanol was characterized by thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Density functional theory (DFT) computations were performed to study the interactions between [EtMIM]Cl and chitobiose. Five kinds of hydrogen bonds, C-H/O, O-H/O, O-H/Cl, C-H/Cl, N-H/Cl were found, suggesting strong interactions between [EtMIM]Cl and chitobiose. In particular, the oxygen atom and the active methylene group of carboxylic ester in [EtMIM]+, formed strong hydrogen bonding with chitobiose. The molecular simulation results indicated that both the Cl− anions and [EtMIM]+ cation played important roles in the chitosan dissolution process, by the disruption of native hydrogen bonds of chitosan.

Theoretical investigation of molecular interactions between sulfur ylide and hypohalous acids (HOX, X═F, Cl, Br, and I)

ABSTRACTIn the present study, the complexes of sulfur ylide (SY) with hypohalous acids (HOX; X═F, Cl, Br, and I) were theoretically studied using the MP2/aug-cc-pVTZ computational level. Four types of structures were obtained for these complexes including two kinds of hydrogen bonds (HBs) (SY: HOX─I and SY: HOX─II) and two kinds of halogen bonds (SY: XOH─I and SY: XOH─II). According to the energetic results, the SY:XOH─I complexes are stronger for X═Br and I, while the SY:HOX─I complexes are favorable for X═Cl and Br; also, the SY:HOX─II complexes are stronger than SY:XOH─II except for SY:IOH─II, which is stronger than its counterpart (SY:HOI─II). Moreover, on comparing SY:HOX─I and II HBs complexes, the former is more stable than the latter, while between the SY:XOH─I and II halogen bond complexes (X═Cl, Br, and I), the SY:XOH─I ones are more stable. The strength, properties, and nature of interactions were also analyzed using the natural bond orbital and atoms in molecules theories.

Red-Shifting versus Blue-Shifting Hydrogen Bonds: Perspective from Ab Initio Valence Bond Theory.

Both proper, red-shifting and improper, blue-shifting hydrogen bonds have been well-recognized with enormous experimental and computational studies. The current consensus is that there is no difference in nature between these two kinds of hydrogen bonds, where the electrostatic interaction dominates. Since most if not all the computational studies are based on molecular orbital theory, it would be interesting to gain insight into the hydrogen bonds with modern valence bond (VB) theory. In this work, we performed ab initio VBSCF computations on a series of hydrogen-bonding systems, where the sole hydrogen bond donor CF3H interacts with ten hydrogen bond acceptors Y (═NH2CH3, NH3, NH2Cl, OH(-), H2O, CH3OH, (CH3)2O, F(-), HF, or CH3F). This series includes four red-shifting and six blue-shifting hydrogen bonds. Consistent with existing findings in literature, VB-based energy decomposition analyses show that electrostatic interaction plays the dominating role and polarization plays the secondary role in all these hydrogen-bonding systems, and the charge transfer interaction, which denotes the hyperconjugation effect, contributes only slightly to the total interaction energy. As VB theory describes any real chemical bond in terms of pure covalent and ionic structures, our fragment interaction analysis reveals that with the approaching of a hydrogen bond acceptor Y, the covalent state of the F3C-H bond tends to blue-shift, due to the strong repulsion between the hydrogen atom and Y. In contrast, the ionic state F3C(-) H(+) leads to the red-shifting of the C-H vibrational frequency, owing to the attraction between the proton and Y. Thus, the relative weights of the covalent and ionic structures essentially determine the direction of frequency change. Indeed, we find the correlation between the structural weights and vibrational frequency changes.

Studies on the halogen substituted β-amino acids and their Cu(II) coordination complexes in crystallography

Halogen substituted β-amino acids, D,L-3-amino-3-(4-fluoro)phenylpropionic acid(D,L-HL1, 1) and D,L-3-amino-3-(4-bromo)phenylpropionic acid(D,L-HL2, 2), as well as their Cu(II) coordination complexes [Cu(L1)2(CH3OH)2]·2CH3OH(3) and [Cu(L2)2(CH3OH)2]·2CH3OH(4) were investigated and their single crystal structures were discussed in details. Supramolecular helical chains were found in β-amino acids 1 and 2 while there was no helix in their coordination complexes 3 and 4. The formation of supramolecular helixes could be due to the hydrogen bonds between terminal ―NH 3 + and adjacent ―COO– in β-amino acids 1 and 2. While, this kind of hydrogen bonds could not be observed in their Cu(II) coordination complexes 3 and 4, in which central-symmetrical dimers could be formed via coplanar coordinated bonds(N―Cu―O) between ―NH2 and ―COO–.

Syntheses, Crystal Structures, and Thermal Properties of Two Transition Metal Complexes With 4-Chlorobenzenesulfonyl-glycine Acid Ligand

Two new transition metal complexes [Cu(4-Cbsgly)(phen)]·0.5H2O (1), [Ni(4-Cbsgly)(phen)2]·3H2O (2) [4-CbsglyH2 = (4-chlorobenzenesulfonyl-glycine acid, phen = 1,10-phenanthroline) were synthesized and characterized by elemental analysis, IR, TG analysis, and single-crystal X-ray diffraction. The complexes 1 and 2 are assembled by various kinds of hydrogen bonds and π-π stacking interactions into the 1D chain and 2D layer, respectively. Two-dimensional layer in 2 are further connected to form sandwich-like structure through weak O–H···O and C–H···O interactions. Furthermore, the thermal stability of complexes 1 and 2 were investigated.

Synthesis of calcium oxalate trihydrate: New data by vibrational spectroscopy and synchrotron X-ray diffraction

Calcium oxalate is found in nature in three different crystalline states determined by the number of H2O in the unit formula (whewellite CaC2O4·H2O, COM; weddellite CaC2O4·(2+x)H2O, COD and caoxite CaC2O4·3H2O, COT). The properties of these materials are relevant in the field of biomedicine, cultural heritage and mineralogy. In two previous papers, we have used X-ray diffraction and vibrational spectroscopy (infrared and Raman) to derive information on crystal and molecular structures of COM and COD. In this paper, we complete the synthesis and analysis on the third form, COT, and present a comparative study of the data collected from the three crystalline states. The experiments clearly highlight the role played by the H2O molecules linked within the structure by different kinds of hydrogen bonds. The vibrational assignment of the infrared and Raman bands are critically proposed. The fact relevant for the work in biomedicine, cultural heritage and crystallography is that a simple examination of the spectra allows quickly to determine the chemical nature of the material in an unknown sample even in a minute quantity or in awkward experimental conditions.

Car-Parrinello Molecular Dynamics Simulations of Infrared Spectra of Crystalline Vitamin C with Analysis of Double Minimum Proton Potentials for Medium-Strong Hydrogen Bonds.

We studied proton dynamics of a hydrogen bonds of the crystalline l-ascorbic acid. Our approach was based on the Car-Parrinello molecular dynamics. The focal point of our study was simulation of the infrared spectra of l-ascorbic acid associated with the O-H stretching modes that are very sensitive to the strength of hydrogen bonding. In the l-ascorbic acid there are four kinds of hydrogen bonds. We calculated their spectra by using anharmonic approximation and the time course of the dipole moment function as obtained from the Car-Parrinello simulation. The quantization of the nuclear motion of the protons was made to perform detailed analysis of strength and properties of hydrogen bonds. We presented double minimum proton potentials with small value of barriers for medium-strong hydrogen bonds. We have also shown the difference character of medium-strong hydrogen bonds compared to weaker hydrogen bonds in the l-ascorbic acid.

X-ray diffraction, spectroscopic (IR, Raman) and DSC studies of bis(betainium) p-toluenesulfonate monohydrate crystal

Bis(betainium) p-toluenesulfonate monohydrate (abbreviated as BBTSH) was studied at various temperatures by X-ray diffraction, differential scanning calorimetry and vibrational spectroscopy methods. DSC curves of BBTSH show a peak at about 349K which corresponds to water escape from the crystal, and reveal the “cold crystallization” phenomenon. BBTSH crystallizes in the P21/c space group of monoclinic system. After heating above 349K the compound dehydrates, the crystal system changes to triclinic, the monocrystalline samples become non-merohedral twins. The BBTSH crystal comprises p-toluenesulfonic anions, monoprotonated betaine dimers and water molecules. Three kinds of hydrogen bonds are present in the crystal: strong, asymmetric and almost linear OH⋯O hydrogen bond (R(O⋯O)=2.463(2)Å), weak OwH⋯O hydrogen bonds (R(Ow⋯O)=2.820(2)−2.822(2)Å) and weak CH⋯O hydrogen bonds (R(C⋯O)=3.295(2)−3.416(2)Å). The νaOHO vibration of the strongest hydrogen bond in the crystal gives rise to an intense broad absorption with numbers of transmission windows in the low wavenumber region of the infrared spectra. Coupling between νCO stretching vibrations of two COO groups of the betaine dimer was detected. The process corresponding to the loss of water is accompanied by the breakage of strong OH⋯O hydrogen bonds in betaine dimers and rearrangement inside half of the betaine dimers. This rearrangement results in formation of the new betaine dimers with OH∙∙∙O hydrogen bond of similar strength as corresponding bond in the hydrated form (BBTSH).

FTIR study of hydrogen bonds in coal under drop weight impact testing.

There are many hydrogen bonds in coal, which affect the chemical structure and properties of coal. FTIR has been applied to the characterization study of the hydrogen bonds of Dongpang coals, which were under drop weight impact. There exists five kinds of hydrogen bonds in the coal: free OH groups, OH...π, OH...OH, cyclic OH tetramers and OH...N. Absorption strength of intermolecular hydrogen bonds markedly declined after impact. Free OH groups mechanical-power chemical reacted in drop weight impact testing. The infrared spectrum were curve-resolved into their component bands. The absorption strength of various hydrogen bonds decreased with the increase of impact energy, but the trend was slowing. By statistical relationship between then, we find then complying with power function relationship. By comparing the exponents of fitted equations, we concluded that failure sensitivity sequence of hydrogen bonds to the impact: free OH groups > cyclic OH tetramers > OH...N > OH...π > OH...OH.