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Kumaran M, Sivaranjani T, Suresh S, Periandy S, Soundhariya S, Alibrahim KA, Alodhayb AN. Investigation of the molecular structure of CHBP, biological activities and SARS-CoV-2 protein binding interaction by molecular and biomolecular spectroscopy approaches. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 322:124853. [PMID: 39053114 DOI: 10.1016/j.saa.2024.124853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 07/10/2024] [Accepted: 07/19/2024] [Indexed: 07/27/2024]
Abstract
The objective of this investigation is to learn more about the structural, electrical, spectroscopic, and physiochemical characteristics of biologically active cyano-4'-hydroxybiphenyl (CHBP). The title molecule's optimized conformational analysis was computed using the DFT/B3LYP/6-311++G (d, p) level of theory. The observed wavenumbers were compared with theoretical FT-IR and FT-Raman spectra. 1H and 13C NMR experimental spectra in CDCl3 solution (solvent phase) were recorded and the chemical shift was calculated. NBO analysis was used to examine the transfer of charge as well as the intermolecular and intramolecular bonding of orbitals. The TD-DFT (time-dependent DFT) approach was used to estimate theoretical values for both the gas and solvent (ethanol) in the corresponding transitional research, which was conducted using UV-Vis's spectra. Energy gap (Eg = 0.26764 eV) implies that the strong potential for charge transfer, and the stability of the CHBP compound. CHBP compound's has bioactive nature, its drug-likeness and biological properties were evaluated. The predicted topological polar surface area of 44.02 \AA2 for the molecule falls within the permissible range of < 140 \AA2. Based on the docking results, the most stable docking score value is -6.84 kcal/mol. In that interaction, MET 165 affects both phenyl rings in a pi-sulphur fashion and a single bond hydrogen with protein moieties GLN 192. This suggests that the pi-alkyl in PRO 168 is a hydroxyl substitutional ring. Our findings demonstrate the CHBP compound is a good inhibitor against the SAR COVID-19 viral protein.
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Affiliation(s)
- M Kumaran
- Department of Physics, Sri ManakulaVinayagar Engineering College, Pondicherry 605107, India
| | - T Sivaranjani
- Department of Physics, Sri ManakulaVinayagar Engineering College, Pondicherry 605107, India.
| | - S Suresh
- Department of Physics, Saveetha Engineering College (Autonomous), Thandalam, Chennai 602105, Tamil Nadu, India.
| | - S Periandy
- Department of Physics, Kanchi Mamunivar Centre for Post Graduate Studies and Research, Pondicherry, India
| | - S Soundhariya
- Department of Physics, Kanchi Mamunivar Centre for Post Graduate Studies and Research, Pondicherry, India
| | - Khuloud A Alibrahim
- Department of Chemistry, College of Science, Princess Nourah bint Abdulrahman University, Riyadh 11671, Saudi Arabia
| | - Abdullah N Alodhayb
- Department of Physics and Astronomy, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
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Kavimani M, Balachandran V, Narayana B, Vanasundari K, Revathi B. Quantum chemical calculation (RDG) of molecular structural evaluation, Hirshfeld, DSSC and docking studies of 4-nitrophenylacetic acid. J Mol Struct 2017. [DOI: 10.1016/j.molstruc.2017.07.094] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Balachandran V, Karpagam V, Revathi B, Kavimani M, Ilango G. Conformational stability, spectroscopic and computational studies, HOMO-LUMO, NBO, ESP analysis, thermodynamic parameters of natural bioactive compound with anticancer potential of 2-(hydroxymethyl)anthraquinone. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 150:631-640. [PMID: 26093112 DOI: 10.1016/j.saa.2015.06.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 07/12/2014] [Accepted: 06/01/2015] [Indexed: 06/04/2023]
Abstract
Natural product drugs play a dominant role in pharmaceutical care. Nature is an attractive source of new therapeutic candidate compounds as a tremendous chemical diversity is found in millions of species of plants, animals, marine organism and micro-organism. A antifungal activity against important opportunist micro-organism and against those involved in superficial mycosis, all from nosocomial origin. The acute in vitro cytotoxicity evaluation of each anthraquinone (AQ) isolated from these bioactive extracts, on a mammalian eukaryotic cell line (Vero cells), allowed us to establish the non-cytotoxic concentration range, which was used to evaluate the anti-microbial effect. A comprehensive ab initio calculation using the DFT/6-31+G(d) level theory showed that 2-(hydroxymethyl)anthraquinone can exist in four possible conformations, which can interchange through the OH group on the five-membered ring. Density functional theory calculations were used to predict the vibrational frequencies and to help in normal mode, assignments. Furthermore, a natural bond orbital analysis was performed describing each hydrogen bond as donor accepter interaction. The Fourier transform infrared spectra (4000-400 cm(-1)) and the Fourier transform Raman spectra (3500-100 cm(-1)) of the HMA in the solid space have been recorded. The calculated HOMO and LUMO energies show that charge transfer occurs within the molecule. The calculated ESP contour map shows the electrophilic and nucleophilic region of the molecule.
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Affiliation(s)
- V Balachandran
- Centre for Research, Department of Physics, A.A. Government Arts College, Musiri, Tiruchirappalli 621211, India.
| | - V Karpagam
- Department of Physics, Sri Saradha College for Women, Perambalur 621212, India
| | - B Revathi
- Centre for Research, Department of Physics, A.A. Government Arts College, Musiri, Tiruchirappalli 621211, India
| | - M Kavimani
- Centre for Research, Department of Physics, A.A. Government Arts College, Musiri, Tiruchirappalli 621211, India
| | - G Ilango
- Department of Physics, M.I.E.T. Engineering College, Tiruchirappalli 620 007, India
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Leela JSPP, Hemamalini R, Muthu S, Al-Saadi AA. Spectroscopic investigation (FTIR spectrum), NBO, HOMO-LUMO energies, NLO and thermodynamic properties of 8-Methyl-N-vanillyl-6-nonenamideby DFT methods. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 146:177-186. [PMID: 25813174 DOI: 10.1016/j.saa.2015.03.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2014] [Revised: 01/23/2015] [Accepted: 03/01/2015] [Indexed: 06/04/2023]
Abstract
Capsicum a hill grown vegetable is also known as red pepper or chili pepper. Capsaicin(8-Methyl-N-vanillyl-6-nonenamide) is the active component in chili peppers, which is currently used in the treatment of osteoarthritis, psoriasis and cancer. Fourier transform infrared (FT-IR) spectrum of Capsaicin in the solid phase were recorded in the region 4000-400 cm(-1) and analyzed. The vibrational frequencies of the title compound were obtained theoretically by DFT/B3LYP calculations employing the standard 6-311++G(d,p) basis set and were compared with Fourier transform infrared spectrum. Complete vibrational assignment analysis and correlation of the fundamental modes for the title compound were carried out. The vibrational harmonic frequencies were scaled using scale factor, yielding a good agreement between the experimentally recorded and the theoretically calculated values. Stability of the molecule arising from hyper conjugative interactions, charge delocalization and intra molecular hydrogen bond-like weak interaction has been analyzed using Natural bond orbital (NBO) analysis by using B3LYP/6-311++G(d,p) method. The results show that electron density (ED) in the σ∗ and π∗ antibonding orbitals and second-order delocalization energies E (2) confirm the occurrence of intra molecular charge transfer (ICT) within the molecule. The dipole moment (μ), polarizability (α) and the hyperpolarizability (β) values of the molecule has been computed. Thermodynamic properties (heat capacity, entropy and enthalpy) of the title compound at different temperatures were calculated.
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Affiliation(s)
| | - R Hemamalini
- PG & Research Department of Physics, Queen Mary's College, Tamilnadu, India
| | - S Muthu
- Department of Physics, Sri Venkateswara College of Engineering, Sriperumpudur 602105, Tamilnadu, India.
| | - Abdulaziz A Al-Saadi
- Department of Chemistry, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia
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Raja B, Balachandran V, Revathi B. Structural study, NCA, FT-IR, FT-Raman spectral investigations, NBO analysis, thermodynamic functions of N-acetyl-l-phenylalanine. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 138:283-295. [PMID: 25498825 DOI: 10.1016/j.saa.2014.11.051] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Revised: 10/23/2014] [Accepted: 11/20/2014] [Indexed: 06/04/2023]
Abstract
The FT-IR and FT-Raman spectra of N-acetyl-l-phenylalanine were recorded and analyzed. Natural bond orbital analysis has been carried out for various intramolecular interactions that are responsible for the stabilization of the molecule. HOMO-LUMO energy gap has been computed with the help of density functional theory. The statistical thermodynamic functions (heat capacity, entropy, vibrational partition function and Gibbs energy) were obtained for the range of temperature 100-1000K. The polarizability, first hyperpolarizability, anisotropy polarizability invariant has been computed using quantum chemical calculations. The infrared and Raman spectra were also predicted from the calculated intensities. Comparison of the experimental and theoretical spectra values provides important information about the ability of the computational method to describe the vibrational modes.
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Affiliation(s)
- B Raja
- Department of Physics, Government Arts College, Kulithalai 639120, Karur, India
| | - V Balachandran
- Research Department of Physics, A.A. Government Arts College, Musiri 621211, India.
| | - B Revathi
- Research Department of Physics, A.A. Government Arts College, Musiri 621211, India
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Kanaani A, Ajloo D, Ghasemian H, Kiyani H, Vakili M, Mosallanezhad A. Synthesis, molecular structure, spectroscopic investigations and computational studies of (E)-1-(4-(4-(diethylamino)-2-hydroxybenzylideneamino)phenyl)ethanone. Struct Chem 2015. [DOI: 10.1007/s11224-015-0571-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Vinod KS, Periandy S, Govindarajan M. Spectroscopic analysis of cinnamic acid using quantum chemical calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 136 Pt B:808-817. [PMID: 25315873 DOI: 10.1016/j.saa.2014.09.098] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2014] [Revised: 09/04/2014] [Accepted: 09/22/2014] [Indexed: 06/04/2023]
Abstract
In this present study, FT-IR, FT-Raman, (13)C NMR and (1)H NMR spectra for cinnamic acid have been recorded for the vibrational and spectroscopic analysis. The observed fundamental frequencies (IR and Raman) were assigned according to their distinctiveness region. The computed frequencies and optimized parameters have been calculated by using HF and DFT (B3LYP) methods and the corresponding results are tabulated. On the basis of the comparison between computed and experimental results assignments of the fundamental vibrational modes are examined. A study on the electronic and optical properties; absorption wavelengths, excitation energy, dipole moment and frontier molecular orbital energies, were performed by HF and DFT methods. The alternation of the vibration pattern of the pedestal molecule related to the substitutions was analyzed. The (13)C and (1)H NMR spectra have been recorded and the chemical shifts have been calculated using the gauge independent atomic orbital (GIAO) method. The Mulliken charges, UV spectral analysis and HOMO-LUMO analysis of have been calculated and reported. The molecular electrostatic potential (MEP) was constructed.
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Affiliation(s)
- K S Vinod
- Department of Physics, Indira Gandhi Polytechnic College, Mahe, UT-Puducherry, India; Research Scholar, Bharathiar University, Coimbatore, Tamil Nadu, India
| | - S Periandy
- Department of Physics, Tagore Arts College, Puducherry, India
| | - M Govindarajan
- Department of Physics, Bharathidasan College for Women, Puducherry, India.
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Arivazhagan M, Manivel S, Jeyavijayan S, Meenakshi R. Vibrational spectroscopic (FTIR and FT-Raman), first-order hyperpolarizablity, HOMO, LUMO, NBO, Mulliken charge analyses of 2-ethylimidazole based on Hartree-Fock and DFT calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 134:493-501. [PMID: 25048284 DOI: 10.1016/j.saa.2014.06.108] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 06/07/2014] [Accepted: 06/16/2014] [Indexed: 06/03/2023]
Abstract
The FTIR and FT-Raman spectra of 2-ethylimidazole (2EIDZ) have been recorded in the region 4000-400 cm(-1) and 3500-50 cm(-1), respectively. Utilizing the observed FTIR and FT-Raman data, a complete vibrational assignment and analysis of the fundamental modes of the compound were carried out. The optimized molecular geometry, harmonic vibrational frequencies, infrared intensities and Raman scattering activities, were calculated by ab initio Hartree-Fock (HF) and density functional theory (DFT/B3LYP) methods with 6-311++G(d,p) basis set. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. A detailed interpretation of the infrared and Raman spectra of 2EIDZ is also reported based on total energy distribution (TED). The values of the total dipole moment (μ) and the first-order hyperpolarizability (β) of the compound were computed. Stability of the molecule arising from hyperconjugative interactions, charge delocalization have been analyzed using natural bond orbital (NBO) analysis. Besides, HOMO and LUMO analysis, Mulliken's charge analysis and several thermodynamic properties have been calculated.
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Affiliation(s)
- M Arivazhagan
- Department of Physics, A.A. Govt. Arts College, Musiri 621 211, India.
| | - S Manivel
- Department of Physics, A.A. Govt. Arts College, Musiri 621 211, India
| | - S Jeyavijayan
- Department of Physics, J.J. College of Engineering and Technology, Tiruchirappalli 620 009, India
| | - R Meenakshi
- Department of Physics, Cauvery College for Women, Tiruchirappalli 620 018, India
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Arivazhagan M, Kavitha R, Subhasini VP. Conformational analysis, UV-VIS, MESP, NLO and NMR studies of 6-methoxy-1,2,3,4-tetrahydronaphthalene. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 128:701-710. [PMID: 24699289 DOI: 10.1016/j.saa.2014.02.102] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Revised: 01/28/2014] [Accepted: 02/16/2014] [Indexed: 06/03/2023]
Abstract
The detailed HF and B3LYP/6-311++G(d,p) comparative studies on the complete FT-IR and FT-Raman spectra of 6-methoxy-1,2,3,4-tetrahydronaphthalene [MTHN] have been studied. In view of the special properties and uses, the present investigation has been undertaken to provide a satisfactorily vibrational analysis of 6-methoxy-1,2,3,4-tetrahydronaphthalene. Therefore, a thorough Raman, IR, molecular electrostatic potential (MESP), non-linear optical (NLO) properties, UV-VIS, HOMO-LUMO and NMR spectroscopic investigation are reported complemented by B3LYP theoretical predictions with basis set 6-311++G(d,p) to provide novel insight on vibrational assignments and conformational stability of MTHN. Potential energy surface scans (PES) of the CH3 group are undertaken to shed light on the rather complicated conformational interchanges in the compound under investigation.
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Affiliation(s)
- M Arivazhagan
- Department of Physics, A.A. Government Arts College, Pulivalam Road, Musiri 621 201, India.
| | - R Kavitha
- Department of Physics, Saranathan College of Engineering, Trichy 620 012, India
| | - V P Subhasini
- Department of Physics, Jeppiaar Engineering College, Chennai 600 119, India
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Balachandran V, Karunakaran V. Molecular structure, vibrational spectroscopic, hyperpolarizability, natural bond orbital analysis, frontier molecular orbital analysis and thermodynamic properties of 2,3,4,5,6-pentafluorophenylacetic acid. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 127:473-483. [PMID: 24662720 DOI: 10.1016/j.saa.2014.02.129] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2013] [Revised: 01/31/2014] [Accepted: 02/19/2014] [Indexed: 06/03/2023]
Abstract
The FT-IR (4000-400cm(-)(1)) and FT-Raman spectra (3500-100cm(-)(1)) of 2,3,4,5,6-pentafluorophenylacetic acid (PAA) have been recorded. Density functional theory calculation with LSDA/6-31+G(d,p) and B3LYP/6-31+G(d,p) basis sets have been used to determine ground state molecular geometries (bond lengths and bond angles), harmonic vibrational frequencies, infrared intensities, Raman intensities and bonding features of the title compound. The assignments of the vibrational spectra have been carried out with the help of normal coordinate analysis (NCA) following the scaled quantum mechanical force field (SQMFF) methodology. The first order hyperpolarizability (β0) and related properties (β, α0 and Δα) of PAA are calculated using B3LYP/6-31+G(d,p) method on the finite-field approach. The calculated first hyperpolarizability shows that the molecule is an attractive molecule for future applications in non-linear optics. The stability of molecule has been analyzed by using NBO analysis. The calculated HOMO and LUMO energies show that charge transfer occurs within this molecule. Mulliken population analysis on atomic charges is also calculated. Thermodynamic properties (heat capacity, enthalpy, Gibb's free energy and entropy) of the title compound at different temperatures were calculated.
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Affiliation(s)
- V Balachandran
- Centre for Research, Department of Physics, AA Government Arts College, Musiri 621 211, India.
| | - V Karunakaran
- PG and Research Department of Physics, Government Arts College, Ariyalur 621 713, India
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Muthu S, Renuga S. Molecular orbital studies (hardness, chemical potential, electronegativity and electrophilicity), vibrational spectroscopic investigation and normal coordinate analysis of 5-{1-hydroxy-2-[(propan-2-yl)amino]ethyl}benzene-1,3-diol. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 118:683-694. [PMID: 24096064 DOI: 10.1016/j.saa.2013.09.035] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 09/01/2013] [Accepted: 09/07/2013] [Indexed: 06/02/2023]
Abstract
FT-IR and FT-Raman spectra of 5-{1-hydroxy-2-[(propan-2-yl) amino] ethyl} benzene-1,3-diol (abbrevi- 54 ated as HPAEBD) were recorded in the region 4000-450 cm(-1) and 4000-100 cm(-1) respectively. The structure of the molecule was optimized and the structural characteristics were determined by density functional theory (B3LYP) and HF method with 6-31 G(d,p) as basis set. The theoretical wave numbers were scaled and compared with experimental FT-IR and FT-Raman spectra. A detailed interpretation of the vibrational spectra of this compound has been made on the basis of the calculated Potential energy distribution (PED). Stability of the molecule arising from hyperconjugation and charge delocalization is confirmed by the natural bond orbital analysis (NBO). The results show that electron density (ED) in the σ antibonding orbitals and E (2) energies confirm the occurrence of intra molecular charge transfer (ICT) within the molecule. The molecule orbital contributions were studied by using the total (TDOS), sum of α and β electron (αβDOS) density of States. Mulliken population analysis of atomic charges is also calculated. The calculated HOMO and LUMO energy gap shows that charge transfer occurs within the molecule. The electron density-based local reactivity descriptors such as Fukui functions were calculated to explain the chemical selectivity or reactivity site in this compound. On the basis of vibrational analyses, the thermodynamic properties of title compound at different temperatures have been calculated.
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Affiliation(s)
- S Muthu
- Department of Physics, Sri Venkateswara College of Enginnering, Sriperumbudur 602105, Tamil Nadu, India.
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Muthu S, Elamurugu Porchelvi E. Experimental spectroscopic (FTIR, FT-Raman, FT-NMR, UV-Visible) and DFT studies of 1-ethyl-1,4-dihydro-7-methyl-4oxo-1,8 napthyridine-3-carboxylic acids. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 116:220-235. [PMID: 23948564 DOI: 10.1016/j.saa.2013.07.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Revised: 06/30/2013] [Accepted: 07/16/2013] [Indexed: 06/02/2023]
Abstract
The solid phase FTIR and FT-Raman spectra of 1-ethyl-1,4-dihydro-7-methyl-4oxo-1,8 napthyridine-3-carboxylic acid (EDMONCA) have been recorded in the regions 4000-500 and 4000-400 cm(-1) respectively. The equilibrium geometry, harmonic vibrational frequencies have been investigated by DFT/B3LYP and B3PW91 methods with 6-311G (d,p) basis set. The different between the observed and scaled wave number values of most of the fundamental is very small. The assignments of the vibrational spectra have been carried out with the aid of normal coordinate analysis (NCA) following the scaled quantum mechanical force field methodology (SQMFFM). Stability of the molecule arising from hyper conjugative interactions, charge delocalization has been analyzed using natural bond orbital (NBO) analysis. UV-Visible spectrum of the compound was recorded and the electronic properties HOMO and LOMO energies were measured. The electric dipole moment (μD) and first hyperpolarizability (βtot) values of the investigated molecule were computed using ab initio quantum mechanical calculations. The calculated results also show that the EDMONCA molecule may have microscopic nonlinear optics (NLO) behavior with non-zero values. (1)H and (13)C NMR spectra were recorded and (1)H and (13)C nuclear magnetic resonance chemical shift of the molecule were calculated using the gauge independent atomic orbital (GIAO) method. Thermal stability of EDMONCA was studied by thermogravimetric analysis (TGA). Next Fukui function was calculated to explain the chemical selectivity or reactivity site in EDMONCA. Finally molecular electrostatic potential (MEP) and other molecular properties were performed.
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Affiliation(s)
- S Muthu
- Department of Physics, Sri Venkateswara College of Engg., Sriperumbudur 602105, Tamil Nadu, India.
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Prasath M, Muthu S, Arun Balaji R. Vibrational spectroscopy investigation using ab initio and DFT vibrational analysis of 7-chloro-2-methylamino-5-phenyl-3H-1,4-benzodiazepine-4-oxide. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 113:224-235. [PMID: 23732619 DOI: 10.1016/j.saa.2013.04.104] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 04/20/2013] [Accepted: 04/24/2013] [Indexed: 06/02/2023]
Abstract
The FT-IR and FT-Raman spectrum of 7-chloro-2-methylamino-5-phenyl-3H-1, 4-benzodiazepine-4-oxide (7CMP4BO) has been recorded in the region 4000-400 and 4000-100 cm(-1) respectively. The optimized geometry, Thermodynamic properties, NBO, Molecular Electrostatic Potentials, PES, frequency and intensity of the vibrational bands of 7CMP4BO were obtained by the ab initio HF and density functional theory (DFT), B3LYP/6-31G (d,p) basis set. The molecule orbital contributions were studied by using the total (TDOS), partial (PDOS), and overlap population (OPDOS) density of states. The harmonic vibrational frequencies were calculated and the scaled values have been compared with experimental FT-IR and FT-Raman spectra. A detailed interpretation of the vibrational spectra of this compound has been made on the basis of the calculated potential energy distribution (PED). The linear polarizability (α) and the first order hyperpolarizability (β) values of the investigated molecule have been computed using DFT quantum mechanical calculations. The observed and the calculated frequencies are found to be in good agreement. The experimental spectra also coincide satisfactorily with those of theoretically calculated values.
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Affiliation(s)
- M Prasath
- Department of Physics, Manonmaniam Sundaranar University, Tirunelveli, Tamilnadu, India
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Muthu S, Paulraj EI. Molecular structure and spectroscopic characterization of ethyl 4-aminobenzoate with experimental techniques and DFT quantum chemical calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 112:169-181. [PMID: 23666352 DOI: 10.1016/j.saa.2013.04.024] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 03/17/2013] [Accepted: 04/02/2013] [Indexed: 06/02/2023]
Abstract
The FT-IR and FT-Raman spectra of ethyl 4-aminobenzoate (EAB) in the solid phase were recorded. The fundamental vibrational wavenumbers, intensities of vibrational bands and the optimized geometrical parameters of the compound were evaluated using DFT (B3LYP) method with 6-311++G(d,p) basis set. The stable geometry of the compound was determined from the potential energy surface scan. Complete vibrational assignments and Natural Bond Orbital (NBO) analysis for the title compound were carried out. The assignments of the vibrational spectra were carried out with the help of normal co-ordinate analysis (NCA) following the Scaled Quantum Mechanical Force Field (SQMFF) methodology. The molecule orbital contributions were studied by using the total (TDOS), partial (PDOS), and overlap population (OPDOS) density of states. UV-visible spectrum of the compound was recorded and the electronic properties, such as HOMO and LUMO energies were performed by time-dependent DFT (TD-DFT) approach. Mulliken population analysis on atomic charges were also calculated. Besides, molecular electrostatic potential (MEP) and thermodynamic properties were performed.
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Affiliation(s)
- S Muthu
- Department of Applied Physics, Sri Venkateswara College of Engineering, Sriperumbudur 602 105, Tamil Nadu, India
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α-Bromo-p-tolunitrile: Conformational stability, vibrational spectroscopic studies, NBO analysis and thermodynamic functions based on density functional theory. J Mol Struct 2013. [DOI: 10.1016/j.molstruc.2013.03.040] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Isac Paulraj E, Muthu S. Spectroscopic studies (FTIR, FT-Raman and UV), potential energy surface scan, normal coordinate analysis and NBO analysis of (2R,3R,4R,5S)-1-(2-hydroxyethyl)-2-(hydroxymethyl) piperidine-3,4,5-triol by DFT methods. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 108:38-49. [PMID: 23454843 DOI: 10.1016/j.saa.2013.01.061] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Revised: 01/02/2013] [Accepted: 01/18/2013] [Indexed: 06/01/2023]
Abstract
This work presents the characterization of (2R,3R,4R,5S)-1-(2-hydroxyethyl)-2-(hydroxymethyl)piperidine-3,4,5-triol (abbreviated as HEHMPT) by quantum chemical calculations and spectral techniques. The spectroscopic properties were investigated by FT-IR, FT-Raman and UV-Vis techniques. The FT-IR spectrum (4000-400 cm(-1)) and FT-Raman spectrum (4000-100 cm(-1)) in solid phase was recorded for HEHMPT. The UV-Vis absorption spectrum of the HEHMPT that dissolved in water was recorded in the range of 100-400 nm. The structural and spectroscopic data of the molecule were obtained from B3LYP and M06-2X with 6-31G(d,p) basis set calculations. The theoretical wavenumbers were scaled and compared with experimental FT-IR and FT-Raman spectra. The complete assignments were performed on the basis of the normal co-ordinate analysis (NCA), experimental results and potential energy distribution (PED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method, interpreted in terms of fundamental modes. The stable geometry of the compound has been determined from the potential energy surface scan. The stability of molecule has been analyzed by NBO analysis. The molecule orbital contributions were studied by using the total (TDOS), partial (PDOS), and overlap population (OPDOS) density of states. The electronic properties like UV spectral analysis and HOMO-LUMO energies were reported. The calculated HOMO and LUMO energies shows that charge transfer interactions taking place within the molecule. Mulliken population analysis on atomic charges is also calculated.
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Affiliation(s)
- E Isac Paulraj
- Manonmaniam Sundaranar University, Tirunelveli 627 012, Tamil Nadu, India.
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Brock DS, Mercier HPA, Schrobilgen GJ. [H(OXeF2)n][AsF6] and [FXeII(OXeIVF2)n][AsF6] (n = 1, 2): Examples of Xenon(IV) Hydroxide Fluoride and Oxide Fluoride Cations and the Crystal Structures of [F3Xe---FH][Sb2F11] and [H5F4][SbF6]·2[F3Xe---FH][Sb2F11]. J Am Chem Soc 2013; 135:5089-104. [DOI: 10.1021/ja312493j] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- David S. Brock
- Department of Chemistry, McMaster University, Hamilton, Ontario L8S 4M1, Canada
| | | | - Gary J. Schrobilgen
- Department of Chemistry, McMaster University, Hamilton, Ontario L8S 4M1, Canada
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Karunakaran V, Balachandran V. α-Bromo-2,6-dichlorotoluene: molecular structure, vibrational spectroscopy, natural bond orbital analysis and NMR studies. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2012; 95:64-72. [PMID: 22613125 DOI: 10.1016/j.saa.2012.04.071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2012] [Revised: 04/04/2012] [Accepted: 04/14/2012] [Indexed: 06/01/2023]
Abstract
The FT-IR and FT-Raman spectra of α-bromo-2,6-dichlorotoluene (αBDCT) have been recorded. The structural and spectroscopic data of the molecule in the ground state have been calculated using Hartree Fock (HF) and Density Functional Theory (DFT)/B3LYP with the standard 6-31++G(d,p) basis set. The optimized molecular geometry, vibrational frequencies and atomic charges in the ground state are calculated. With the help of specific scaling procedures, the observed vibrational wavenumbers in FT-IR and FT-Raman spectra have been analyzed and assigned to different normal modes of the molecule. A detailed interpretation of the infrared and Raman spectra of αBDCT is also reported based on total energy distribution (TED). The (1)H and (13)C NMR chemical shifts have been calculated by gauge-including atomic orbital method with B3LYP/6-31++G(d,p) approach. Stability of the molecule arising from hyperconjugative interactions and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The theoretical results agree well with the observed spectra.
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Affiliation(s)
- V Karunakaran
- Research Department of Physics, Government Arts College, Ariyalur 621713, India
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Molecular structure, vibrational spectroscopic, NBO, HOMO–LUMO and Mulliken analysis of 4-methyl-3-nitro benzyl chloride. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2011.12.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Balachandran V, Parimala K. Molecular structure, vibrational spectra, NBO analysis, first hyperpolarizability, and HOMO, LUMO studies of mesityl chloride by density functional methods. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2011.10.035] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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Nagabalasubramanian PB, Periandy S, Mohan S. Ab initio HF and DFT simulations, FT-IR and FT-Raman vibrational analysis of alpha-chlorotoluene. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2010; 77:150-159. [PMID: 20537941 DOI: 10.1016/j.saa.2010.04.043] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Revised: 03/04/2010] [Accepted: 04/30/2010] [Indexed: 05/29/2023]
Abstract
The FT-IR and FT-Raman vibrational spectra of alpha-chlorotoluene have been recorded using Perkin-Elmer 180 spectrometer in the range 3600-10 cm(-1) in the solid phase. A detailed vibrational spectral analysis has been carried out and assignments of the observed fundamental bands have been proposed on the basis of peak positions and relative intensities. The optimized molecular geometry, vibrational frequencies, atomic charges, dipole moment, rotational constants and several thermodynamic parameters in the ground state were calculated using ab initio Hartree-Fock (HF) and Density Functional B3LYP methods (DFT) with 6-311G(d) and 6-311++G(d) basis sets. With the help of specific scaling procedures, the observed vibrational wavenumbers in FT-IR and FT-Raman spectra were analyzed and assigned to different normal modes of the molecule. Most of the modes have wavenumbers in the expected range. The results of the calculations were applied to simulated infrared and Raman spectra of the title compound which showed excellent agreement with the observed spectra.
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Affiliation(s)
- P B Nagabalasubramanian
- Department of Physics, Arignar Anna Govt Arts College, 21 Perumal Koil Street, Karaikal 609 602, India.
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Sundaraganesan N, Elango G, Meganathan C, Karthikeyan B, Kurt M. Molecular structure, vibrational spectra and HOMO, LUMO analysis of 4-piperidone by density functional theory andab initioHartree–Fock calculations. MOLECULAR SIMULATION 2009. [DOI: 10.1080/08927020902873992] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Song YZ, Zhu AF, Lv JS, Gong GX, Xie JM, Zhou JF, Ye Y, Zhong XD. Synthesis and theoretical studies on the vibration of a novel (3,4-disfluoro)phenylquione. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2009; 73:96-100. [PMID: 19268627 DOI: 10.1016/j.saa.2009.01.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2008] [Revised: 01/07/2009] [Accepted: 01/27/2009] [Indexed: 05/27/2023]
Abstract
A novel (3,4-disfluoro)phenylquione (2F-PQ) was synthesized through the reaction of 3,4-Difluoroaniline and 1,4-benzoquinone. Its structure was verified by (1)H NMR, FTIR and Raman spectra. The ground-state geometries were optimized by using density functional theory (DFT) at B3LYP/6-311G+(d,p), B3PW91/6-311G+(d,p) and MPB3PW91/6-311G+(d,p) level without symmetry constrains, respectively. The predicted FTIR and Raman spectra scaled by factor are well consistent with experimental spectra.
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Affiliation(s)
- Yuan-zhi Song
- Key Laboratory for Chemistry of Low-Dimensional Materials, Jiangsu Province, Chemistry Department, Huaiyin Teachers College, Huaian, 223300, People's Republic of China
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Sundaraganesan N, Umamaheswari H, Meganathan C, Sebastian S. Molecular structure and vibrational spectra of 4-nitrobenzylchloride by ab initioHartree–Fock and density functional methods. MOLECULAR SIMULATION 2008. [DOI: 10.1080/08927020802036013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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