HF Levels Research Articles

Static (hyper)polarizabilities and absorption spectra of single [2.2]p-cyclophane NO2/NH2 substituted from DFT methods

We explore the behavior of the average of polarizability ( ), total first hyperpolarizability (βtotal) and average of second hyperpolarizability ( ) for single A/D (-NO2/-NH2) substituted [2.2]p-cyclophane. The geometric optimization was carried out at HF and DFT (SVWN, PBE, B3LYP, PBE0, BHHLYP and CAM-B3LYP) level, in gas phase, using the 6-31 + G(d,p) basis set. The static tensor components of and βtotal, in gas phase, were calculated using Field Finite (FF) methods with electric field intensities of E = ± 0.001 a.u. in each (x,y,z) axis direction. The substitution of A/D groups in positions 7–15 (structure 2 in Fig. 1) produced an increment in the values. Regardless of the A/D positions, the values showed not significant changes at all theory level. DFT results are overestimated up to 20%, if HF values are taken into account, being SVWN and PBE functionals those that give the main deviation. There are monotonic and progressive behaviors of βtotal for the 1–5 structure change as expected by orientation of the dipolar moment in both aromatic rings. With respect to the performance of DFT functionals, and βtotal results are significantly overestimated if HF values are taken into account. In fact, the relative percentage error of βtotal at DFT level with respect to HF ones is between 58 and 132%, being PBE functional those that give the main deviation. The close overlap of the orbitals between the rings facilitates chromophore delocalization to account for the observation of high βtotal in these compounds. Therefore, we expected that the contribution by coupling of the transition moment between first and higher excited states should be lie much higher due to phane effect than that for ring units. Open image in new window Fig. 1 a Single [2.2]p-cyclophane core molecule. b Geometric parameters of interest c Highlights for the 4, 7, 12, and 15 positions, which are substituted by (-NO2/-NH2) acceptor/donor pair

DFT study of isomers of the ruthenium dihydride complex RuH2(CO)2(AsMe2Ph)2.

A density functional theory (DFT) study of cct-As, ccc, and cct-CO isomers of the ruthenium dihydride complex RuH2(CO)2(AsMe2Ph)2 is reported (see Scheme for the labeling isomer 34 structures of RuH2(CO)2(AsMe2Ph)2). Complex geometries and relative energies of different isomers have been calculated with both B3LYP and M06-2X functionals. The results show that the B3LYP calculated Boltzmann populations of cct-As, ccc, and cct-CO isomers are 65.5, 34.2, and 0.3%, respectively. These are in better agreement with the experimental data than those calculated at the M06-2X level. However, the calculations of 1H NMR chemical shifts were found to be better described with M06-2X than with B3LYP or with HF level of theories. In addition, a transition state between the two most stable isomers was determined through DFT/(B3LYP or M06-2X) calculations. Graphical Abstract Scheme: Labeling structure of RuH2(CO)2(AsMe2Ph)2.

GALECTIN-3 AND NT-proBNP AS BIOMARKERS OF HEART FAILURE DECOMPENSATION

Aim. To compare the levels of galectin-3 and N-terminal brain natriuretic peptide precursor (NT-proBNP) in heart failure patients with saved ejection fraction of the left ventricle (HF-sEF) and heart failure with low ejection fraction (HF-lEF). To study the possibilities for implementation of galectin-3 and NT-proBNP as markers of HF decompensation in HF-sEF Material and methods. Totally, 30 patients with HF-sEF included (17 females, 13 males, mean age 65±8 y.o.) and 30 patients with HF-lEF (11 females, 19 males, mean age 63±11 y.o.). All patients underwent physical examination, 6-minute walking test, clinical condition assessment by clinical condition score (CCS), echocardiography (Echo), tissue doppler imaging, measurement of galectin-3 and NT-proBNP levels at admission. Results. The difference of mean levels of NT-proBNP in HF-sEF and HF-lEF did not differ significantly (153,23±114,44 fM/ml and 142,45±90,82 fM/ml, resp., t=0,4, p=0,68). A direct correlation was found for HF clinics in both groups (r=0,46, p<0,05, 95% CI). In HF-sEF the negative correlation was found for the mean level of NT-proBNP and 6-minute walking test results by CCS, direct correlation between clinical condition of patients by CCS (r=0,048, p=0,02, 95% CI), direct correlation of clinical presentation and real systolic pressure in in pulmonary artery (r=0,4, p=0,03, 95% CI); negative correlation of the mean NT-proBNP and peak A velocity (r=-0,52, p=0,003, 95% CI). Mean level of galectin-3 in blood plasma in HF-sEF (0,98±1,93 hg/mL) is significantly higher than in HF-lEF (0,13±0,07 ng/mL) (t=2,41, p=0,01). There was no relation found for the main clinical presentation of HF and galectin-3 level in HF patients. In both groups there was no relation between the mean galectin-3 level and 6-minute test, and clinical condition by CCS. There was positive relation of ejection fraction of the left ventricle by Echo and mean level of galectin-3 (r=0,45, p=0,012, 95% CI). Conclusion. The level of NT-proBNP does not differ in HF-sEF and HF-lEF patients and is related to the severity of CHF. Therefore, NT-proBNP might be used as a marker of CHF decompensation. Level of galecton-3 is significantly higher in HFsEF patients and does not relate on severity of CHF. Both markers can be used for diagnostics of CHF patients and to reveal HF-sEF before Echo is done.

Nano-sized NaF inspired intrinsic solvothermal growth mechanism of rare-earth nanocrystals for facile control synthesis of high-quality and small-sized hexagonal NaYbF4:Er

Facile solvothermal control synthesis of hexagonal NaYbF4:Er was achieved by simultaneous regulation of nano-sized NaF and HF levels based on the findings of NaOH to nano-sized NaF conversion via reacting with NH4F and decomposition of NH4F to HF.

Conformational and electronic properties of N-methacryloyl-(L)-glutamic acid

ABSTRACTConformers of N-methacryloyl-(L)-glutamic acid (MAGA, C9H13NO5) in the gas phase, benzene or methanol environment were searched by the density functional theory (DFT) and time-dependent DFT. Selected conformational isomers based on potential energy surface analysis were studied by considering the structural and electronic properties. B3LYP functional, and HF and MP2 levels were used with the 6-31+G(d,p), 6-311+G(3df,p) and aug-cc-pVDZ basis sets. We explored the effect of medium on the conformational preferences, UV spectra and frontier molecular orbitals of the conformers. The outcomes of this research will be useful for future studies including moieties analogous to MAGA.

Crystal Structure, Hirshfeld Surface Analysis and Computational Studies of Thiazolidin-4-one derivative: (Z)-5-(4-Chlorobenzylidene)-3-(2-ethoxyphenyl)-2-thioxothiazolidin-4-one.

The title compound (Z)-5-(4-chlorobenzylidene)-3-(2-ethoxyphenyl)-2-thioxothiazolidin-4-one (CBBTZ) was characterized by X-ray single crystal diffraction, 1H NMR and 13C NMR spectra. Theoretical investigations were carried out using HF and DFT levels of theory at 6-31G(d,p) basis set. The X-ray structure is compared with that computed. The calculated geometrical parameters are in good agreement with those determined by X-ray diffraction. The dihedral angle between the two benzene rings is 16.89(5)° indicating that the structure is non planar. The molecule exhibits intraand intermolecular contacts of type C-H···O, C-H···S and C-H···Cl. The intercontacts in the crystal structure are explored using Hirshfeld surfaces analysis method.

QSPR Modeling of Heat Capacity, Thermal Energy and Entropy of Aliphatic Aldehydes by using Topological Indices and MLR Method

Quantitative Structure-Property Relationship (QSPR) models are useful in understanding how chemical structure relates to the physicochemical properties of natural and synthetic chemicals. In the present investigation the applicability of various topological indices are tested for the QSPR study on 24 aldehydes. The topological indices used for the QSPR analysis were Randic () (the first order molecular connectivity), Balaban (J), Wiener (W) and Harary (H) indices. In this study, the relationship between the topological indices to the thermal energy (Eth), heat capacity (Cv) and entropy(S) of 24 aldehydes are established. The thermodynamic properties are taken from HF level using the ab initio 6-31 G basis sets from the program package Gussian 98. For obtaining appropriate QSPR model we have used multiple linear regression (MLR) techniques and followed Back ward regression analysis. The results have shown that combining the three descriptors (J, W, ) could be used successfully for modeling and predicting the heat capacity (CV), two descriptors (J, 1) could be efficiently used for estimating the entropy (S) and one descriptors () could be predict the thermal energy of compounds.

Solution to the π-Distortivity Problem.

Traditionally, the delocalized π system of benzene is believed to be responsible for its perfectly symmetric D6h geometry. However, it has also been suggested that the π system prefers a distorted D3h geometry. Arguments for this have been based on clever use of VB methods as well as through shifts in the frequency of the distortive b2u mode. Evidence has been provided through different ways of partitioning the total electronic energy between the σ and the π systems. These methods are plagued by the fact that there is no unique way to partition the energy, leading to questions regarding the validity of the conclusions. Here we note that even though energy cannot be partitioned exactly, force acting on a nucleus depends only on the single particle density and can hence be partitioned exactly. Using good-quality wave functions that are numerically found to obey the Hellmann-Feynman theorem to good accuracy, we calculate the σ and π components of the force and provide conclusive evidence of π-distortivity at the HF level. Our approach provides an unambiguous way to approach the problem with wave functions that account for electron correlation. Our calculations suggest that the conclusion is valid at the MP2 level, too.

Correlation consistent basis sets for lanthanides: The atoms La–Lu

Using the 3rd-order Douglas-Kroll-Hess (DKH3) Hamiltonian, all-electron correlation consistent basis sets of double-, triple-, and quadruple-zeta quality have been developed for the lanthanide elements La through Lu. Basis sets designed for the recovery of valence correlation (defined here as 4f5s5p5d6s), cc-pVnZ-DK3, and outer-core correlation (valence + 4s4p4d), cc-pwCVnZ-DK3, are reported (n = D, T, and Q). Systematic convergence of both Hartree-Fock and correlation energies towards their respective complete basis set (CBS) limits are observed. Benchmark calculations of the first three ionization potentials (IPs) of La through Lu are reported at the DKH3 coupled cluster singles and doubles with perturbative triples, CCSD(T), level of theory, including effects of correlation down through the 4s electrons. Spin-orbit coupling is treated at the 2-component HF level. After extrapolation to the CBS limit, the average errors with respect to experiment were just 0.52, 1.14, and 4.24 kcal/mol for the 1st, 2nd, and 3rd IPs, respectively, compared to the average experimental uncertainties of 0.03, 1.78, and 2.65 kcal/mol, respectively. The new basis sets are also used in CCSD(T) benchmark calculations of the equilibrium geometries, atomization energies, and heats of formation for Gd2, GdF, and GdF3. Except for the equilibrium geometry and harmonic frequency of GdF, which are accurately known from experiment, all other calculated quantities represent significant improvements compared to the existing experimental quantities. With estimated uncertainties of about ±3 kcal/mol, the 0 K atomization energies (298 K heats of formation) are calculated to be (all in kcal/mol): 33.2 (160.1) for Gd2, 151.7 (-36.6) for GdF, and 447.1 (-295.2) for GdF3.

A theoretical conformational study on the structural parameters involved in the ring strain of exo-unsaturated four-membered heterocycles, Y = CCH2CH2X

ABSTRACTThe effect of ring-puckering angle on the structural parameters (bond lengths and angles) involved in the ring strain of a series of four-membered heterocycles (1–16) was theoretically demonstrated by using the ab initio methods MP2 and HF, and the DFT methods PBE1PBE, B3LYP, SVWN5 with 6-31+G(d,p) as basis set. The results revealed that the bonds within the ring (C–X and C–C) are the most sensitive to puckering angle changes. The variation of the C–X and C=Y bond lengths as function of puckering angle are determined by a balance between the 1,3 repulsive interactions and the electronic nature of the heteroatoms X and Y. Particularly, for azetidines and phosphetanes, the C–X and C=Y bond lengths exhibit a major increase at axial conformations. In general, the C–C bond length decreases with the puckering angle for all heterocycles. While the heteroatom–H bonds (in the ring skeleton) are very sensitive to geometric changes, exhibiting an increasing behaviour for equatorial conformations and a decreasing behaviour for axial conformations highly puckered (ϕ > −20°). The C–X–C angle decreases monotonically with the puckering angle, increasing the Baeyer strain on the studied molecules. Finally, all methods predicted a similar behaviour for the studied parameters as function of the puckering angle, although some smaller differences in the predictions of their respective values, especially at HF level, were observed.

QSPR study on benzene derivatives to some physico-chemical properties by using topological indices

QSPR study on benzene derivatives have been made using recently introduced topological methodology. In this study the relationship between the Randic' (x'), Balaban (J), Szeged (Sz),Harary (H), Wiener (W), HyperWiener and Wiener Polarity (WP) to the thermal energy (Eth), heat capacity (CV) and entropy (S) of benzene derivatives is represented. Physicochemical properties are taken from the quantum mechanics methodology with HF level using the ab initio 6-31G basis sets. The multiple linear regressions (MLR) and back ward methods (with significant at the 0.05 level) were employed to give the QSPR models. The satisfactory obtained results show that combining the two descriptors (Sz, HW) are useful topological descriptors for predicted (CV) and (S) of the 45 benzene derivatives. The training set models established by MLR method have not good correlation of (Eth), which means QSPR models could not predict the thermal energy of compounds.

Modeling emission features of salicylidene aniline molecular crystals: A QM/QM' approach.

A new computational protocol relying on the use of electrostatic embedding, derived from QM/QM' ONIOM calculations, to simulate the effect of the crystalline environment on the emission spectra of molecular crystals is here applied to the β-form of salicylidene aniline (SA). The first singlet excited states (S1 ) of the SA cis-keto and trans-keto conformers, surrounded by a cluster of other molecules representing the crystalline structure, were optimized by using a QM/QM' ONIOM approach with and without electronic embedding. The model system consisting of the central salicylidene aniline molecule was treated at the DFT level by using either the B3LYP, PBE0, or the CAM-B3LYP functional, whereas the real system was treated at the HF level. The CAM-B3LYP/HF level of theory provides emission energies in good agreement with experiment with differences of -20/-32 nm (cis-keto form) and -8/-14 nm (trans-keto form), respectively, whereas notably larger differences are obtained using global hybrids. Though such differences on the optical properties arise from the density functional choice, the contribution of the electronic embedding is rather independent of the functional used. This plays in favor of a more general applicability of the present protocol to other crystalline molecular systems.

Comprehensive Study on The Solvation of Sr(II) Ion

Solvation of Sr 2+ ion in liquid ammonia has been studied using the HF, DFT (B3LYP), second-order Moller-Plesset (MP2) and CCSD theory. Single valence basis sets were applied. Total and sequential binding energies are evaluated for all strontium-ammonia clusters containing 1-6 ammonia molecules. Total binding energies and distance calculated using the high level G09 calculations. For each addition of an ammonia molecules, the change of the Sr-N distance in metal-ammonia clusters is the highest at the HF level. HF is the best compromise between computational effort and accuracy.

Cheminformatics and System Chemistry of Cisplatin, Carboplatin, Nedaplatin, Oxaliplatin, Heptaplatin and Lobaplatin as Anti-Cancer Nano Drugs: A Combined Computational and Experimental Study

The anti-cancer Nano drugs Cisplatin, Carboplatin, Nedaplatin, Oxaliplatin, Heptaplatin and Lobaplatin were characterized by 1HNMR, 13CNMR, 31PNMR, Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR), FT-Raman, HR Mass and UV-Vis spectroscopies and also by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), Differential Thermal Analysis-Thermal Gravim Analysis (DTA-TGA), Energy-Dispersive X-Ray Spectroscopy (EDX) and XRay Diffraction (XRD) analysis and crystallography. Ab initio and Density Functional Theory (DFT) calculations have been carried out for the title anti-cancer Nano drugs by performing HF, PM3, MM2, MM3, AM1, MP2, MP3, MP4, CCSD, CCSD(T), LDA, BVWN, BLYP and B3LYP levels of theory using the standard 31G, 6-31G*, 6-31+G*, 6-31G(3df, 3pd), 6-311G, 6-311G* and 6-311+G* basis sets of the Gaussian 09. The computational results show that the predicted geometries can well reproduce the structural, thermodynamic and spectroscopic parameters. Predicted vibrational frequencies have been assigned and compared with experimental 1HNMR, 13CNMR, 31PNMR, Attenuated Total Reflectance Fourier Transform Infrared (ATRFTIR), FT-Raman, HR Mass and UV-Vis spectra and they are supported each other comparison between the experimental and the computational results indicates that ab initio and Density Functional Theory (DFT) HF, PM3, MM2, MM3, AM1, MP2, MP3, MP4, CCSD, CCSD(T), LDA, BVWN, BLYP and B3LYP levels of theory using the standard 31G, 6-31G*, 6-31+G*, 6-31G(3df, 3pd), 6-311G, 6-311G* and 6-311+G* basis sets of the Gaussian 09 are able to provide satisfactory results for predicting dynamic NMR shielding tensors and vibrational frequencies properties. On the basis of vibrational analyses, the structural, thermodynamic and spectroscopic properties of the title anti-cancer Nano drugs at different temperatures have been calculated.

Development of a Program to Calculate Vibrational Scale Factor

Vibrational molecular spectroscopy is an important tool to assess a substance structural properties, even allowing its identification. The resulting spectra vary in complexity, according to the molecule´s degrees of freedom. Currently, a number of software packages are available to simulate molecular vibrations, correlating the observed modes with the corresponding wavenumbers, while also allowing a visual depiction of atom displacement. Calculated spectra are useful to help with the interpretation of experimental ones. However, available methods have their own limitations, yielding over- or underestimated wavenumbers, which can be circumvented by applying a suitable scale factor. In this work we developed a FORTRAN code to automatically calculate scale factors. We also obtained experimental infrared spectra of thymol and the aminoacids D-valine, L-phenylalanine, D- phenylalanine, D- glutamic acid. Calculated spectra were obtained using G.A.M.E.S.S. at HF, MP2 and DFT (B3LYP) level of theory, with 6-31G(d,p) basis set. The data thus obtained was input to the program, which gave the corresponding scale factor quickly and close to those reported in the literature. DOI: 10.5935/1984-6835.20160023

The Correlation of PPARα Activity and Cardiomyocyte Metabolism and Structure in Idiopathic Dilated Cardiomyopathy during Heart Failure Progression.

This study aimed to define relationship between PPARα expression and metabolic-structural characteristics during HF progression in hearts with DCM phenotype. Tissue endomyocardial biopsy samples divided into three groups according to LVEF ((I) 45–50%, n = 10; (II) 30–40%, n = 15; (III) <30%, n = 15; and control (donor hearts, >60%, n = 6)) were investigated. The PPARα mRNA expression in the failing hearts was low in Group (I), high in Group (II), and comparable to that of the control in Group (III). There were analogous changes in the expression of FAT/CD36 and CPT-1 mRNA in contrast to continuous overexpression of GLUT-4 mRNA and significant increase of PDK-4 mRNA in Group (II). In addition, significant structural changes of cardiomyocytes with glycogen accumulation were accompanied by increased expression of PPARα. For the entire study population with HF levels of FAT/CD36 mRNA showed a strong tendency of negative correlation with LVEF. In conclusion, PPARα elevated levels may be a direct cause of adverse remodeling, both metabolic and structural. Thus, there is limited time window for therapy modulating cardiac metabolism and protecting cardiomyocyte structure in failing heart.

Structure, adhesion and corrosion behavior of CrN/TiN superlattice coatings deposited by the combined deep oscillation magnetron sputtering and pulsed dc magnetron sputtering

Abstract Deep oscillation magnetron sputtering (DOMS) is a novel high power impulse magnetron sputtering technique, which offers large voltage oscillation packets to generate a stable high-power discharge plasma with high ionization under virtually arc-free conditions. CrN/TiN superlattice coatings with various modulated periods (Λ) were deposited by the combined DOMS and pulsed dc magnetron sputtering. CrN/TiN superlattice coatings with the Cr/(Cr + Ti) ratio ranging from 0.177 to 0.496 exhibited a single phase face-centered cubic structure with a strong (111) texture. As the Λ was increased from 5.7 to 10.2 nm, the residual stress was increased from − 2.1 to − 5.6 GPa. The increase in Λ led to an initial increase, followed by a decrease in hardness, and the H/E* and H3/E*2 ratios. The coating at Λ = 6.3 nm showed the highest adhesion with the highest HF level in Rockwell C tests and critical loads in scratch tests due to the highest hardness of 36 GPa, H/E* ratio of 0.093 and H3/E*2 ratio of 0.316. The predominant adhesive failure mode in scratch tests was buckling failure independent of the changes of Λ and substrate hardness. However, the increase in substrate hardness resulted in an increase in critical loads (LC1, LC2, LC3 and LC4), especially for a significant increase in LC3, due to the increased cooperative deformation of a coating/substrate system by increasing toughness of coatings, cohesion/adhesion and substrate hardness. The increased adhesion was responsible for the increased pitting and stress corrosion cracking resistance in 3.5 wt.% NaCl aqueous solution due to the optimized Cr/(Cr + Ti) ratio and Λ.

Mechanical and tribological properties of CrN/TiN multilayer coatings deposited by pulsed dc magnetron sputtering

CrN/TiN multilayer coatings were deposited by pulsed dc magnetron sputtering (PDCMS) in a closed field unbalanced magnetron sputtering system. The Ti target power was maintained at 2000W while the Cr target power was varied from 70 to 1000W. As the Cr target power was increased, CrN/TiN multilayer coatings with the Cr/(Cr+Ti) ratio of 0.037–0.573 had a single phase face-centered cubic structure with a texture evolution from (111) to (220). The residual stress of the coatings increased from −1.03GPa to −5.65GPa. The hardness and the H/E* and H3/E*2 ratios of the coatings exhibited an initial increase with the increasing Cr target power, then followed by a decrease. The coating with a Cr/(Cr+Ti) ratio of 0.30 reached the highest hardness and the H/E* and H3/E*2 ratios of 31GPa, 0.0832 and 0.214, respectively. The coating also showed a dominant oxidative wear with the lowest friction coefficient and specific wear rate of 0.41 and 2.3×10−6mm3N−1m−1, respectively. The increase in the H/E* and H3/E*2 ratios led to the increase in the toughness and cohesion/adhesion strength of the coatings with the increased HF levels and critical loads (LC1, LC2 and LC3). However, the coatings with similar H/E* and H3/E*2 ratios exhibited different tribological properties due to the different critical loads LC3 resulted from the increased compressive residual stress. The improvements in toughness and cohesion/adhesion strength promoted the reduction in the crack initiation and propagation, and oxidative wear during dry sliding tests.

FT-IR, HOMO–LUMO, NBO, MEP analysis and molecular docking study of 3-Methyl-4-{(E)-[4-(methylsulfanyl)-benzylidene]amino}1H-1,2,4-triazole-5(4H)-thione

FT-IR spectrum of 3-Methyl-4-{(E)-[4-(methylsulfanyl)-benzylidene]amino}1H-1,2,4-triazole-5(4H)-thione was recorded and analysed. The vibrational wavenumbers were computed and at HF and DFT levels of theory. The data obtained from wavenumber calculations are used to assign the vibrational bands obtained in the IR spectrum. The NH stretching wavenumber is red shifted in the IR spectrum from the computed value, which indicates the weakening of the NH bond. The geometrical parameters of the title compound are in agreement with the XRD results. NBO analysis, HOMO–LUMO, first and second order hyperpolarizability and molecular electrostatic potential results are also reported. From the MEP map it is evident that the negative regions are localized over the sulphur atoms and N3 atom of triazole ring and the maximum positive region is localized on NH group, indicating a possible site for nucleophilic attack. Prediction of Activity Spectra analysis of the title compound predicts anti-tuberculostic activity with probability to be active value of 0.543. Molecular docking studies reveal that the triazole nitrogen atoms and the thione sulphur atom play vital role in bonding and results draw us to the conclusion that the compound might exhibit anti-tuberculostic activity.

A comprehensive study of the structure, tautomeric properties, and conformational flexibility of 3-Hydroxy-propeneselenal

In the present work, a conformational analysis of 3-Hydroxy-propeneselenal is performed using several computational methods, including HF, DFT (B3LYP), and G2MP2 levels of theory. The relative electronic energies, the molecular structure, and intramolecular hydrogen bond energies are reported. Twenty different conformers were obtained, the most stable ones being planar. The conformational preference of this molecule was found to be mainly determined by the formation of Se...H-O and Se-H...O intramolecular hydrogen bonds, which are assisted by π-electron resonance. The atoms in molecules (AIM) theory of Bader, which is based on topological properties of the electron density, was used to analyze critical points and to study the nature of hydrogen bonds in these systems. NMR and natural bond orbital (NBO) analyses were also performed for a better understanding of the nature of intramolecular interactions in 3-Hydroxy-propeneselenal. Furthermore, calculations for all the possible conformations of the title compound in solution were also carried out at the B3LYP/6-311 ++G(d,p) level of theory (in three models such as polarizable continuum model (PCM), IEFPCM, and self −consistent isodensity polarized continuum model (SCIPCM). The aim of this work is to highlight the efficiency and suitability of silicadiphenic acid as a supported solid acid catalyst for the synthesis of bis-(indolyl)methane derivatives from a one-pot condensation reaction of various substituted aldehydes and indole in acetonitrile at 60°C.