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Charanya C, Sampathkrishnan S, Balamurugan N. Quantum Chemical Computations, Molecular Docking, Vibrational Spectroscopic Analysis, Non-Linear Optical Properties and DFT Calculation of 2-[(2,3-Dimethylphenyl)Amino]Benzoic Acid. Polycycl Aromat Compd 2019. [DOI: 10.1080/10406638.2019.1700138] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- C. Charanya
- Department of Physics, Sri Venkateshwara College of Engineering, Sriperumbudur, Tamil Nadu, India
| | - S. Sampathkrishnan
- Department of Physics, Sri Venkateshwara College of Engineering, Sriperumbudur, Tamil Nadu, India
| | - N. Balamurugan
- Department of Physics, Dhanalakshmi College of Engineering, Chennai, Tamil Nadu, India
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2
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Korn Taksapattanakul, Tulyapitak T, Phinyocheep P, Ruamcharoen P, Ruamcharoen J, Daniel P. Hydrogenated Natural Rubber as an Alternative Replacement to Ethylene-Propylene-Diene-Monomer (EPDM) Rubber in Terms of Thermal-Oxidative Degradation Properties. POLYMER SCIENCE SERIES B 2019. [DOI: 10.1134/s1560090419050178] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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3
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Srivastava A, Karthick T, Joshi BD, Mishra R, Tandon P, Ayala AP, Ellena J. Spectroscopic (far or terahertz, mid-infrared and Raman) investigation, thermal analysis and biological activity of piplartine. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2017; 184:368-381. [PMID: 28538206 DOI: 10.1016/j.saa.2017.05.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 05/03/2017] [Accepted: 05/04/2017] [Indexed: 06/07/2023]
Abstract
Research in the field of medicinal plants including Piper species like long pepper (Piper longum L.- Piperaceae) is increasing all over the world due to its use in traditional and Ayurvedic medicine. Piplartine (piperlongumine, 5,6-dihydro-1-[(2E)-1-oxo-3-(3,4,5-trimethoxyphenyl)-2-propenyl]-2(1H)-pyridinone), a biologically active alkaloid/amide was isolated from the phytochemical investigations of Piper species, as long pepper. This alkaloid has cytotoxic, anti-fungal, anti-diabetic, anti-platelet aggregation, anti-tumoral, anxiolytic, anti-depressant, anti-leishmanial, and genotoxic activities, but, its anticancer property is the most promising and has been widely explored. The main purpose of the work is to present a solid state characterization of PPTN using thermal analysis and vibrational spectroscopy. Quantum mechanical calculations based on the density functional theory was also applied to investigate the molecular conformation and vibrational spectrum, which was compared with experimental results obtained by Raman scattering, far (terahertz) and mid-infrared adsorption spectroscopy. NBO analysis has been performed which predict that most intensive interactions in PPTN are the hyperconjugative interactions between n(1) N6 and π*(O1C7) having delocalization energy of 50.53kcal/mol, Topological parameters have been analyzed using 'AIM' analysis which governs the three bond critical points (BCPs), one di-hydrogen, and four ring critical points (RCPs). MEP surface has been plotted which forecast that the most negative region is associated with the electronegative oxygen atoms (sites for nucleophilic activity). Theoretically, to confirm that the title compound has anti-cancer, anti-diabetic and anti-platelet aggregation activities, it was analyzed by molecular docking interactions with the corresponding target receptors. The obtained values of H-bonding parameters and binding affinity prove that its anti-cancer activity is the more prominent than the other properties.
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Affiliation(s)
- Anubha Srivastava
- Department of Physics, University of Lucknow, University Road, Lucknow 226 007, Uttar Pradesh, India.
| | - T Karthick
- Department of Physics, University of Lucknow, University Road, Lucknow 226 007, Uttar Pradesh, India
| | - B D Joshi
- Department of Physics, Tribhuvan University, Siddhanath Sc. Campus, Nepal 10400, India; Departamento de Física, Universidade Federal do Ceará, C. P. 6030, 60.455-900 Fortaleza, CE, Brazil
| | - Rashmi Mishra
- Department of Physics, University of Lucknow, University Road, Lucknow 226 007, Uttar Pradesh, India; Department of Physics, Seth G.B. Podar College, Nawalgarh, Rajasthan, India
| | - Poonam Tandon
- Department of Physics, University of Lucknow, University Road, Lucknow 226 007, Uttar Pradesh, India.
| | - A P Ayala
- Departamento de Física, Universidade Federal do Ceará, C. P. 6030, 60.455-900 Fortaleza, CE, Brazil
| | - Javier Ellena
- Instituto de Física de São Carlos, Universidade de São Paulo, CP. 369, 13560-970, São Carlos, SP, Brazil
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Srivastava A, Singh H, Mishra R, Dev K, Tandon P, Maurya R. Structural insights, protein-ligand interactions and spectroscopic characterization of isoformononetin. J Mol Struct 2017. [DOI: 10.1016/j.molstruc.2016.12.043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Iyasamy S, Varadharajan K, Sivagnanam S. Density Functional Theory Calculations, Spectroscopic (FT-IR, FT-RAMAN), Frontier Molecular Orbital, Molecular Electrostatic Potential Analysis of 5-Fluoro-2-Methylbenzaldehyde. Z PHYS CHEM 2016. [DOI: 10.1515/zpch-2016-0839] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The FT-IR and FT-Raman spectra of 5-fluoro-2-methylbenzaldehyde (5F2MB) have been recorded in the regions 4000–400 cm−1 and 4000–100 cm−1, respectively. Using the observed FT-IR and FT-Raman data, a complete vibrational assignment and analysis of the fundamental modes of vibrations of the compound were carried out. The optimum molecular geometry, vibrational frequencies and Raman scattering activities were calculated by density functional theory with B3LYP/6-311+G** basis sets. A close agreement was achieved between the calculated and observed frequencies by refinement of scale factors. Unambiguously normal modes of vibrational assignments have been made with the help of the GUASSVIEW 5.0 program and the potential energy distribution (PED) calculated by the density functional theory calculations. Natural bonding orbital (NBO) analyses were carried out to discuss the stability of the molecule. The molecular electrostatic potential (MEP) map and electron density map were drawn and analyzed. Using nuclear magnetic resonance (NMR) analysis, the chemical shifts of hydrogen atoms and carbon atoms were calculated. The charge distribution, Mullikan atomic charge values and HOMO–LUMO energy have been calculated to explore the reasons for the change in biological activity. Furthermore, the first hyperpolarizability and the dipole moment of the molecule have also been calculated.
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Affiliation(s)
- Sehar Iyasamy
- Department of Physics, Aditanar College of Arts and Science, Tiruchendur, Tamilnadu – 628215, India
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El-Azab AS, Jalaja K, Abdel-Aziz AAM, Al-Obaid AM, Sheena Mary Y, Yohannan Panicker C, Van Alsenoy C. Spectroscopic analysis (FT-IR, FT-Raman and NMR) and molecular docking study of ethyl 2-(4-oxo-3-phenethyl-3,4-dihydroquinazolin-2-ylthio)-acetate. J Mol Struct 2016. [DOI: 10.1016/j.molstruc.2016.05.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Probing the adsorption and orientation of 2,3-dichloro-5,8-dimethoxy-1,4-naphthoquinone on gold nano-rods: A SERS and XPS study. J Mol Struct 2016. [DOI: 10.1016/j.molstruc.2016.02.043] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Velraj G, Soundharam S, Sridevi C. Investigation of structure, vibrational, electronic, NBO and NMR analyses of 2-chloro-4-nitropyridine (CNP), 2-chloro-4-methyl-5-nitropyridine (CMNP) and 3-amino-2-chloro-4-methylpyridine (ACMP) by experimental and theoretical approach. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 137:790-803. [PMID: 25277627 DOI: 10.1016/j.saa.2014.08.075] [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: 05/19/2014] [Revised: 08/07/2014] [Accepted: 08/24/2014] [Indexed: 06/03/2023]
Abstract
This study reports about the optimized molecular structures, vibrational wavenumbers, atomic charges, molecular electrostatic potentials, NBO, electronic properties, (1)H NMR and (13)C NMR chemical shifts for the molecules 2-chloro-4-nitropyridine (CNP), 2-chloro-4-methyl-5-nitropyridine (CMNP) and 3-amino-2-chloro-4-methylpyridine (ACMP). Theoretical calculations were performed by density functional theory (DFT)/B3LYP method using 6-311++G (d,p) basis set. The stability and charge delocalization of the title molecules were studied by natural bond orbital (NBO) analysis. Molecular electrostatic potential maps (MEP) were calculated to predict the reactive sites. The reactivity of the title compounds were investigated by HOMO-LUMO energies and global descriptors. The electronic properties of the compounds were also discussed and the transitions were found to be π→π(∗). In addition, the thermodynamic properties were studied for the title compounds and corresponding relations between the properties and temperature were also discussed. The hyperpolarizability values (βtot) were calculated for the title compounds. Hyperpolarizability value (βtot) of CMNP was found to be high and nineteen times greater than that of urea.
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Affiliation(s)
- G Velraj
- Department of Physics, Periyar University, Salem 636011, Tamil Nadu, India.
| | - S Soundharam
- Department of Physics, Selvamm Arts and Science College (Autonomous), Namakkal 637003, Tamil Nadu, India
| | - C Sridevi
- Department of Physics, Sona College of Technology, Salem 636005, Tamil Nadu, India
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Bhavani K, Renuga S, Muthu S, Sankara Narayanan K. Quantum mechanical study and spectroscopic (FT-IR, FT-Raman, (13)C, (1)H) study, first order hyperpolarizability, NBO analysis, HOMO and LUMO analysis of 2-acetoxybenzoic acid by density functional methods. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 136 Pt C:1260-1268. [PMID: 25456668 DOI: 10.1016/j.saa.2014.10.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2014] [Revised: 07/18/2014] [Accepted: 10/08/2014] [Indexed: 06/04/2023]
Abstract
In this work, colorless crystals of 2-acetoxybenzoic acid were grown by slow evaporation method and the FT-IR and FT-Raman spectra of the sample were recorded in the region 4000-500cm(-1) and 4000-100cm(-1) respectively. Molecular structure is optimized with the help of density functional theory method (B3LYP) with 6-31+G(d,p), 6-311++G(d,p) basis sets. 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 confirms the occurrence of intramolecular charge transfer (ICT) within the molecule. The assignments of the vibrational spectra have been carried out with the help of normal coordinate analysis following the scaled quantum mechanical force field (SQMFF) methodology. The results of the calculations were applied to simulated spectra of the title compound, which show excellent agreement with observed spectra. The (1)H and (13)C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by GIAO method. Mulliken population analysis on atomic charges is also calculated. The calculated HOMO and LUMO energy gap shows that charge transfer occurs within the molecule.
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Affiliation(s)
- K Bhavani
- Department of Physics, SRM University, Chennai, Tamil Nadu, India
| | - S Renuga
- Department of Physics, Indira Institute of Enginnering and Technology, Thiruvallur, Tamil Nadu, India
| | - S Muthu
- Department of Physics, Sri Venkateswara College of Engg, Sriperumbudur 602105, Tamil Nadu, India.
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Polat T, Yurdakul Ş. Quantum chemical and spectroscopic (FT-IR and FT-Raman) investigations of 3-methyl-3h-imidazole-4-carbaldehyde. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 133:683-696. [PMID: 24996210 DOI: 10.1016/j.saa.2014.05.039] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 05/02/2014] [Accepted: 05/09/2014] [Indexed: 06/03/2023]
Abstract
FT-IR and FT-Raman spectra of 3-methyl-3h-imidazole-4-carbaldehyde (3M3HI4C) were recorded in the region 4000-400cm(-1) and 3500-50cm(-1), respectively. Optimized geometric parameters, conformational equilibria, normal mode frequencies, and corresponding vibrational assignments of 3M3HI4C were theoretically examined by quantum chemical methods for the first time. All vibrational frequencies were assigned in detail with the help of total energy distribution (TEDs). The experimental wavenumbers were compared with the scaled vibrational frequencies determined by DFT/B3LYP method. The results showed that the B3LYP/6-311++G(d,p) method predicts vibrational frequencies and the structural parameters effectively. The most stable conformer of the title compound was determined. The total electron density and molecular electrostatic potential surfaces of the molecule were constructed by using B3LYP/6-311++G(d,p) method to display electrostatic potential (electron+nuclei) distribution. The electronic properties HOMO and LUMO energies were measured. The lower energy band was assigned to the HOMO→LUMO transition. Natural bond orbital analysis of title molecule has been performed to indicate the presence of intramolecular charge transfer. Energies, relative stabilities, and dipole moments of title molecule were also compared and analyzed in the gas phase and in solvents. Furthermore, solvent effects on the geometry and vibrational frequency of 3M3HI4C were studied theoretically at the DFT/B3LYP level in combination with the conductor polarizable continuum model (C-PCM).
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Affiliation(s)
- Turgay Polat
- Department of Physics, Faculty of Arts and Sciences, Kastamonu University, Kuzeykent, 37100 Kastamonu, Turkey.
| | - Şenay Yurdakul
- Department of Physics, Faculty of Science, Gazi University, Teknikokullar, 06500 Ankara, Turkey
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Krishna Kumar V, Suganya S, Mathammal R. Molecular structure, vibrational spectra, HOMO, LUMO and NMR studies of 2,3,4,5,6-penta bromo toluene and bromo durene based on density functional calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 125:201-210. [PMID: 24556128 DOI: 10.1016/j.saa.2013.12.070] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Revised: 12/02/2013] [Accepted: 12/11/2013] [Indexed: 06/03/2023]
Abstract
This work deals with the vibrational spectra of 2,3,4,5,6-Penta Bromo Toluene (PBT) and Bromo Durene (BD) by quantum chemical calculations. The solid phase FTIR and FT-Raman spectra of the title compounds were recorded in the regions 4000-400 cm(-1) and 4000-50 cm(-1), respectively. The spectra were interpreted with the aid of normal coordinate analysis based on density functional theory (DFT) using B3LYP/6-31G* level and basis set combinations and was scaled using various scale factors yielding a good agreement between observed and calculated frequencies. The infrared and Raman spectra were also predicted from the calculated intensities. Comparison of the simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes. The HOMO and LUMO energies were calculated within the molecule. (13)C and (1)H NMR chemical shifts results were also calculated and compared with the experimental values. Thermodynamical properties like entropy heat capacity, zero point energy have been calculated for the title molecules.
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Affiliation(s)
- V Krishna Kumar
- Department of Physics, Periyar University, Salem 636011, India.
| | - S Suganya
- Department of Physics, N.K.R. Govt. Arts College (W), Namakkal 637001, India
| | - R Mathammal
- Department of Physics, Sri Sarada College for Women (Autonomous), Salem 636016, India
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12
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Velraj G, Soundharam S, Sridevi C. Structure, vibrational, electronic, NBO and NMR analyses of 3-methyl-2,6-diphenylpiperidin-4-one (MDPO) by experimental and theoretical approach. J Mol Struct 2014. [DOI: 10.1016/j.molstruc.2013.12.040] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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13
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Prabakaran A, Muthu S. Normal coordinate analysis, molecular structure, vibrational and electronic spectral investigation of 7-(1,3-dioxolan-2-ylmethyl)-1,3-dimethylpurine-2,6-dione by ab initio HF and DFT method. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 118:578-588. [PMID: 24095768 DOI: 10.1016/j.saa.2013.09.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2013] [Revised: 08/21/2013] [Accepted: 09/02/2013] [Indexed: 06/02/2023]
Abstract
In the present work, the characterization of 7-(1,3-dioxolan-2-ylmethyl)-1,3-dimethylpurine-2,6-dione (7DDMP26D) molecule was carried out by quantum chemical method and vibrational spectral techniques. The FT-IR (4000-400 cm(-1)) and FT-Raman (4000-100 cm(-1)) spectra of 7DDMP26D were recorded in solid phase. The UV-Vis absorption spectrum of the 7DDMP26D was recorded in the range of 200-400 nm. The molecular geometry, harmonic vibrational frequencies and bonding features of 7DDMP26D in the ground state have been calculated by HF and DFT methods using 6-31G(d,p) basis set. The complete vibrational frequency assignments were made by normal coordinate analysis (NCA) following the scaled quantum mechanical force field methodology (SQMF). The molecular stability and bond strength were investigated by applying the natural bond orbital analysis (NBO). The electronic properties, such as excitation energies, absorption wavelength, HOMO and LUMO energies were performed by time-depended DFT (TD-DFT) approach. The other molecular properties like electrostatic potential (ESP), Fukui function and thermodynamic properties of the title compound at different temperatures have been calculated. Finally, the calculation results were analyzed to simulate infrared, FT-Raman and UV spectra of the title compound which shows better agreement with observed spectra.
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Affiliation(s)
- A Prabakaran
- Department of Physics, Pallavan College of Engg., Kanchipuram 631 502, India; Department of Physics, Bharathiar University, Coimbatore 641 046, India
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Arivazhagan M, Anitha Rexalin D, Geethapriya J. Vibrational spectra, DFT quantum chemical calculations and conformational analysis of P-iodoanisole. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 113:236-249. [PMID: 23727676 DOI: 10.1016/j.saa.2013.04.106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 04/15/2013] [Accepted: 04/24/2013] [Indexed: 06/02/2023]
Abstract
The solid phase FT-IR and FT-Raman spectra of P-iodoanisole (P-IA) have been recorded in the regions 400-4000 and 50-4000 cm(-1), respectively. The spectra were interpreted in terms of fundamentals modes, combination and overtone bands. The structure of the molecule was optimized and the structural characteristics were determined by ab initio (HF) and density functional theory (B3LYP) methods with LanL2DZ as basis set. The potential energy surface scan for the selected dihedral angle of P-IA has been performed to identify stable conformer. The optimized structure parameters and vibrational wavenumbers of stable conformer have been predicted by density functional B3LYP method with LanL2DZ (with effective core potential representations of electrons near the nuclei for post-third row atoms) basis set. The nucleophilic and electrophilic sites obtained from the molecular electrostatic potential (MEP) surface were calculated. The temperature dependence of thermodynamic properties has been analyzed. Several thermodynamic parameters have been calculated using B3LYP with LanL2DZ basis set.
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Affiliation(s)
- M Arivazhagan
- PG & Research Department of Physics, A.A. Government Arts College, Musiri 621 211, Tamil Nadu, India.
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Krishnakumar V, Sangeetha R, Mathammal R, Barathi D. Density functional theory, comparative vibrational spectroscopic studies, HOMO-LUMO, first hyperpolarizability analyses of 2-fluoro 5-nitrotoluene and 2-bromo 5-nitrotoluene. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 104:77-86. [PMID: 23266679 DOI: 10.1016/j.saa.2012.10.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2012] [Revised: 09/23/2012] [Accepted: 10/04/2012] [Indexed: 06/01/2023]
Abstract
This work deals with the vibrational spectra of 2-fluoro 5-nitrotoluene and 2-bromo 5-nitrotoluene by quantum chemical calculations. The solid phase FTIR and FT-Raman spectra of the title compounds were recorded in the regions 4000-400 cm(-1) and 4000-50 cm(-1) respectively. The spectra were interpreted with the aid of normal co-ordinate analysis based on density functional theory (DFT) using standard B3LYP/6-31G(*) basis set for the most optimized geometry. The vibrational frequencies are calculated and scaled values are compared with experimental FTIR and FT-Raman spectra. The scaled theoretical wave numbers showed very good agreement with the experimental ones. The complete vibrational assignments are performed on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. (13)C and (1)H NMR chemical shifts results are compared with the experimental values.
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Affiliation(s)
- V Krishnakumar
- Department of Physics, Periyar University, Salem 636 011, India.
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17
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Prabakaran A, Muthu S. Normal coordinate analysis and vibrational spectroscopy (FT-IR and FT-Raman) studies of (2S)-2-amino-3-(3,4-dihydroxyphenyl)-2-methylpropanoic acid using ab initio HF and DFT method. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2012; 99:90-96. [PMID: 23044411 DOI: 10.1016/j.saa.2012.09.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 08/15/2012] [Accepted: 09/03/2012] [Indexed: 06/01/2023]
Abstract
The FT-IR and FT-Raman spectra of (2S)-2-amino-3-(3,4-dihydroxyphenyl)-2-methylpropanoic acid (2ADMA) were recorded in the region 4000-400 cm(-1) and 4000-100 cm(-1), respectively. The geometrical structure, harmonic vibrational frequency, infrared intensity, Raman activities and bonding features of this compound was carried out by ab initio HF and DFT methods with 6-31G (d,p) basis set. The complete vibrational frequency assignments were made by normal coordinate analysis (NCA) following the scaled quantum mechanical force field methodology (SQMF). The electric dipole moment (μ) and the first-order hyperpolarizability (β(0)) values have been the computed quantum mechanically. The calculated HOMO and LUMO energies show that, the charge transfer occurs within the molecule. The charge delocalizations of these molecules have been analyzed using NBO analysis. The solvent effects have been calculated using TD-DFT in combination with the polarized continuum model (PCM), and the results are in good agreement with experimental measurements. The other molecular properties like Mulliken population analysis, electrostatic potential (ESP) and thermodynamic properties of the title compound at the different temperatures have been calculated. Finally, the calculation results were applied to simulate infrared and Raman spectra of the title compound which shows good agreement with observed spectra.
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Affiliation(s)
- A Prabakaran
- Department of Physics, Pallavan College of Engg., Kanchipuram 631 502, India
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Sridevi C, Panneer Selvam N, Shanthi G, Velraj G. Tautomeric stability, vibrational, electronic, NBO, and NMR analyses of N-[acetylamino-(3-nitrophenyl)methyl]-acetamide (ANPMA) by ab initio HF and DFT calculations. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2012.07.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Sridevi C, Velraj G. Investigation of molecular structure, vibrational, electronic, NMR and NBO analysis of 5-chloro-1-methyl-4-nitro-1H-imidazole (CMNI) using ab initio HF and DFT calculations. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2012.03.040] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Krishnakumar V, Murugeswari K, Prabavathi N, Mathammal R. Molecular structure, vibrational spectra, HOMO, LUMO and NMR studies of 2-chloro-4-nitrotoluene and 4-chloro-2-nitrotoluene. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2012; 91:1-10. [PMID: 22343112 DOI: 10.1016/j.saa.2012.01.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Revised: 12/22/2011] [Accepted: 01/16/2012] [Indexed: 05/31/2023]
Abstract
The solid phase FTIR and FT-Raman spectra of 2-chloro-4-nitrotoluene (2Cl4NT) and 4-chloro-2-nitrotoluene (4Cl2NT) were recorded in the regions 4000-400 cm(-1) and 4000-50 cm(-1) respectively. The fundamental vibrational frequencies and intensities of the vibrational bands were evaluated using density functional theory (DFT) with B3LYP method and standard 6-31G* basis set combinations. The infrared and Raman spectra were also predicted from the calculated intensities. The vibrational spectra were interpreted with the aid of normal coordinate analysis based on a scaled quantum mechanical force field. The calculated HOMO and LUMO energies showed that charge transfer had occurred within the molecule. Comparison of simulated spectra with the experimental spectra provided important information about the ability of the computational method to describe the vibrational modes. (13)C NMR chemical shifts results were also compared with the experimental values.
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Affiliation(s)
- V Krishnakumar
- Department of Physics, Periyar University, Salem 636 011, Tamil Nadu, India.
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Krishnakumar V, Jayamani N, Mathammal R. Molecular structure, vibrational spectral studies of pyrazole and 3,5-dimethyl pyrazole based on density functional calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 79:1959-1968. [PMID: 21703911 DOI: 10.1016/j.saa.2011.05.100] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 05/27/2011] [Accepted: 05/30/2011] [Indexed: 05/31/2023]
Abstract
In this work, the experimental and theoretical vibrational spectra of pyrazole (PZ) and 3,5-dimethyl pyrazole (DMP) have been studied. FTIR and FT-Raman spectra of the title compounds in the solid phase are recorded in the region 4000-400 cm(-1) and 4000-50 cm(-1), respectively. The structural and spectroscopic data of the molecules in the ground state are calculated using density functional methods (B3LYP) with 6-311+G** basis set. The vibrational frequencies are calculated and scaled values are compared with experimental FTIR and FT-Raman spectra. The observed and calculated frequencies are found to be in good agreement. The complete vibrational assignments are performed on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SM) method. 13C and 1H NMR chemical shifts results are compared with the experimental values.
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Affiliation(s)
- V Krishnakumar
- Department of Physics, Periyar University, Salem 636011, India.
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Govindarajan M, Ganasan K, Periandy S, Karabacak M. Experimental (FT-IR and FT-Raman), electronic structure and DFT studies on 1-methoxynaphthalene. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 79:646-653. [PMID: 21530378 DOI: 10.1016/j.saa.2011.03.051] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2010] [Revised: 03/19/2011] [Accepted: 03/23/2011] [Indexed: 05/30/2023]
Abstract
In this work, FT-IR and FT-Raman spectra of 1-methoxynapthalene (C(11)H(10)O) have been reported in the regions 4000-400 cm(-1) and 3500-100 cm(-1), respectively. Density functional method (DFT) has been used to calculate the optimized geometrical parameters, atomic charges, vibrational wavenumbers and intensity of the vibrational bands. The vibrational frequencies have been calculated and scaled values are compared with experimental FT-IR and FT-Raman spectra. The structure optimizations and normal coordinate force field calculations are based on density functional theory (DFT) method with B3LYP/3-21G, B3LYP/6-31G, B3LYP/6-31G(d,p) and B3LYP/6-311++G(d,p) basis sets. The complete vibrational assignments of wavenumbers are made on the basis of potential energy distribution (PED). The optimized geometric parameters are compared with experimental values of naphthoic acid. The results of the calculation shows excellent agreement between experimental and calculated frequencies in B3LYP/6-311++G(d,p) basis set. The effects due to the substitutions of methyl group and carbon-oxygen bond are also investigated. A study on the electronic properties, such as excitation energies and wavelengths, were performed by time-dependent DFT (TD-DFT) approach. HOMO and LUMO energies are calculated that these energies show charge transfer occurs within the molecule.
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Krishnakumar V, Prabavathi N. Simulation of IR and Raman spectra of p-hydroxyanisole and p-nitroanisole based on scaled DFT force fields and their vibrational assignments. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2009; 74:154-161. [PMID: 19523872 DOI: 10.1016/j.saa.2009.05.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Revised: 05/10/2009] [Accepted: 05/18/2009] [Indexed: 05/27/2023]
Abstract
This work deals with the vibrational spectroscopy of p-hydroxyanisole (PHA) and p-nitroanisole (PNA) by means of quantum chemical calculations. The mid and far FT-IR and FT-Raman spectra were recorded in the condensed state. The fundamental vibrational frequencies and intensity of vibrational bands were evaluated using density functional theory (DFT) with the standard B3LYP/6-31G* method and basis set combination and were scaled using various scale factors which yield a good agreement between observed and calculated frequencies. The vibrational spectra were interpreted with the aid of normal coordinate analysis based on scaled density functional force field. The results of the calculations were applied to simulate infrared and Raman spectra of the title compounds, which showed excellent agreement with the observed spectra.
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Affiliation(s)
- V Krishnakumar
- Department of Physics, Periyar University, Salem 636 011, India
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Siddiqui SA, Dwivedi A, Singh PK, Hasan T, Jain S, Prasad O, Misra N. Molecular structure, vibrational spectra and potential energy distribution of protopine using ab initio and density functional theory. J STRUCT CHEM+ 2009. [DOI: 10.1007/s10947-009-0062-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Krishnakumar V, Prabavathi N, Muthunatesan S. Density functional theory calculations and vibrational spectra of 6-methyl 1,2,3,4-tetrahyroquinoline. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2008; 69:853-9. [PMID: 17625959 DOI: 10.1016/j.saa.2007.05.034] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2007] [Revised: 04/23/2007] [Accepted: 05/07/2007] [Indexed: 05/16/2023]
Abstract
The solid phase FTIR and Raman spectra of 6-methyl 1,2,3,4-tetrahydroquinoline (MTHQ) have been recorded in the regions 4000-100 and 3500-100 cm(-1), respectively. The spectra were interpreted with the aid of normal coordinate analysis following a full structure optimization and force field calculations based on the density functional theory (DFT) using the standard B3LYP/6-311+G(**) basis set combination. A close agreement was achieved between the observed and calculated frequencies by refinement of the scale factors.
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Affiliation(s)
- V Krishnakumar
- Department of Physics, Periyar University, Salem 636011, India.
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Krishnakumar V, Ramasamy R. Density functional and experimental studies on the FT-IR and FT-Raman spectra and structure of 2,6-diamino purine and 6-methoxy purine. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2008; 69:8-17. [PMID: 17466577 DOI: 10.1016/j.saa.2007.02.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2006] [Revised: 02/19/2007] [Accepted: 02/22/2007] [Indexed: 05/15/2023]
Abstract
FT-IR and FT-Raman spectra of 2,6-diamino purine (DAP) and 6-methoxy purine (MP) have been recorded in the regions of 4000-400cm(-1) and 3500-100cm(-1), respectively. The spectra were interpreted with the aid of normal coordinate analysis following full structure optimizations and force field calculations based on density functional theory (DFT) using standard B3LYP/6-31G* and B3LYP/6-311+G** method and basis set combinations. Normal coordinate calculations were performed with the DFT force field corrected by a recommended set of scaling factors yielding fairly good agreement between observed and calculated frequencies.
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Affiliation(s)
- V Krishnakumar
- Department of Physics, Periyar University, Salem 636011, India.
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Pathak A, Agarwal R, Tandon P, Gupta VD. Vibrational Dynamics and Heat Capacity of Trans‐1,4‐Polyisoprene (α‐Form). J MACROMOL SCI B 2007. [DOI: 10.1080/00222340601066907] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Ajita Pathak
- a Department of Physics , University of Lucknow , Lucknow, India
| | - Ruchi Agarwal
- a Department of Physics , University of Lucknow , Lucknow, India
| | - Poonam Tandon
- a Department of Physics , University of Lucknow , Lucknow, India
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Krishnakumar V, Ramasamy R. Vibrational spectra and structure of 5,6-diamino uracil and 5,6-dihydro-5-methyl uracil by density functional theory calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 66:503-11. [PMID: 16920007 DOI: 10.1016/j.saa.2006.02.066] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Accepted: 02/25/2006] [Indexed: 05/11/2023]
Abstract
The molecular vibrations of 5,6-diamino uracil and 5,6-dihydro-5-methyl uracil were investigated in polycrystalline sample, at room temperature, by FT-IR and FT-Raman spectroscopies. The spectra were interpreted with the aid of normal coordinate analysis following a full structure optimization and force field calculations based on the density functional theory (DFT) using standard B3LYP/6-31G* and B3LYP/6-311+G** methods and basis set combinations. The DFT force field transformed to natural internal coordinates was corrected by a well-established set of scale factors that were found to be transferable to the title compounds. The infrared and Raman spectra were also predicted from the calculated intensities. Comparison of the simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes.
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Affiliation(s)
- V Krishnakumar
- Department of Physics, Periyar University, Salem 636011, India.
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Abstract
AbstractThe solid phase FT-IR and FR-Raman spectra of acetyl coumarin have been recorded in the regions 4000–50 cm−1. The spectra were interpreted with the aid of normal coordinate analysis following full structure optimization and force field calculations based on density functional theory (DFT) and Hartree-Fock (HF) at 6–31G* and 6–311++G** basis sets. The resulting force fields were transformed to internal coordinates, the calculated vibrational frequencies and normal modes were utilized in the assignment of the observed vibrational fundamentals. The measured spectral data were used to refine the vibrational force constants by means of a small number of scaling factors.
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Krishnakumar V, Ramasamy R. Scaled quantum chemical studies of the structure and vibrational spectra of 2-(methylthio) benzimidazole. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2005; 62:570-7. [PMID: 16257761 DOI: 10.1016/j.saa.2004.12.052] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2004] [Accepted: 12/16/2004] [Indexed: 05/05/2023]
Abstract
The solid phase FT-IR and FT-Raman spectra of 2-(methylthio) benzimidazole (2-MTBI) have been recorded in the regions 4000-50 cm(-1) and 3500-100 cm(-1), respectively. The spectra were interpreted with the aid of normal coordinate analysis following full structure optimization and force field calculations based on density functional theory (DFT) using standard B3LYP/6-31G* and B3LYP/6-311+G** methods and basis set combinations and was scaled using various scale factors yielding fairly good agreement between observed and calculated frequencies. Based on the present good quality scaled quantum mechanical (SQM) force field, a reliable description of the fundamentals was provided and the assignments have been proposed with the aid of normal coordinate analysis. The infrared and Raman spectra were also predicted from the calculated intensities. Comparison of the simulated spectra with the experimental spectra provides important information about the ability of the computational method to describe the vibrational modes.
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Affiliation(s)
- V Krishnakumar
- Department of Physics, Periyar University, Salem 636011, India.
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Krishnakumar V, John Xavier R. Scaled quantum chemical studies of the structure and vibrational spectra of 2,4-diaminoquinazoline and 4-amino-2-methylquinoline. Chem Phys 2005. [DOI: 10.1016/j.chemphys.2004.11.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Adams MA, Gabrys BJ, Zajac WM, Peiffer DG. High-Resolution Incoherent Inelastic Neutron Scattering Spectra of Polyisobutylene and Polyisoprene. Macromolecules 2004. [DOI: 10.1021/ma049651w] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Mark A. Adams
- The ISIS Pulsed Neutron Scattering Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, U.K.; Department of Materials, University of Oxford, Oxford, OX1 3PH, U.K.; The H. Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland; and ExxonMobil Research and Engineering Co., Annandale, New Jersey 08801
| | - Barbara J. Gabrys
- The ISIS Pulsed Neutron Scattering Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, U.K.; Department of Materials, University of Oxford, Oxford, OX1 3PH, U.K.; The H. Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland; and ExxonMobil Research and Engineering Co., Annandale, New Jersey 08801
| | - Wojciech M. Zajac
- The ISIS Pulsed Neutron Scattering Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, U.K.; Department of Materials, University of Oxford, Oxford, OX1 3PH, U.K.; The H. Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland; and ExxonMobil Research and Engineering Co., Annandale, New Jersey 08801
| | - Dennis G. Peiffer
- The ISIS Pulsed Neutron Scattering Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxon, OX11 0QX, U.K.; Department of Materials, University of Oxford, Oxford, OX1 3PH, U.K.; The H. Niewodniczański Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Kraków, Poland; and ExxonMobil Research and Engineering Co., Annandale, New Jersey 08801
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Determination of the relative reactivities of cis and trans isomers of β-bromostyrene towards polystyryllithium by Raman spectroscopy. J Mol Struct 2004. [DOI: 10.1016/j.molstruc.2004.05.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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36
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Samran J, Phinyocheep P, Daniel P, Kittipoom S. Hydrogenation of unsaturated rubbers using diimide as a reducing agent. J Appl Polym Sci 2004. [DOI: 10.1002/app.20811] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Arjunan V, Subramanian S, Mohan S. Fourier transform infrared and Raman spectral analysis of trans-1,4-polyisoprene. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2001; 57:2547-2554. [PMID: 11765780 DOI: 10.1016/s1386-1425(01)00426-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Polyisoprene is the most widely used polymer in industry and commerce. Fourier transform infrared (FTIR) and Raman spectra of trans-1,4-polyisoprene have been recorded in the range of 4000-400 and 4000-100 cm(-1), respectively. In the present investigation, detailed assignments of the observed fundamental bands of trans-1,4-polyisoprene has been analysed in terms of peak positions and relative intensities. With the hope of providing more and effective information on the fundamental vibrations, a normal co-ordinate analysis has been performed on trans-1,4polyisoprene, by assuming Cs symmetry. The simple general valance force field (SGVFF) method has been employed in normal co-ordinate analysis and to calculate the potential energy distribution (PED) for each fundamental vibration. The PED contribution corresponding to each of the observed frequencies shows the reliability and accuracy of the spectral analysis. The validity of the SGVFF method as a practical tool for complete analysis of vibrational spectra, even for a polymer of this complexity, is confirmed in the present work.
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Affiliation(s)
- V Arjunan
- Department of Chemistry, Pondicherry Engineering College, Pondicherry, India
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38
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Xue G. Fourier transform Raman spectroscopy and its application for the analysis of polymeric materials. Prog Polym Sci 1997. [DOI: 10.1016/s0079-6700(96)00006-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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