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Theoretical studies of molecular structure and vibrational spectra of 2-amino-5-phenyl-1,3,4-thiadiazole
Spectrochimica Acta Part A 64 (2006) 68–72
Theoretical studies of molecular structure and vibrational spectra of 2-amino-5-phenyl-1,3,4-thiadiazole Y. Atalay a , F. Yakuphanoglu b,∗ , M. Sekerci c , D. Avcı a , A. Bas¸o˘glu a a
Sakarya University, Faculty of Arts and Sciences, Department of Physics, Sakarya, Turkey b Firat University, Faculty of Arts and Sciences, Department of Physics, Elazig, Turkey c Firat University, Faculty of Arts and Sciences, Department of Chemistry, Elazig, Turkey Received 8 June 2005; accepted 29 June 2005
Abstract The molecular geometry and vibrational frequencies of 2-amino-5-phenyl-1,3,4-thiadiazole (C8 H7 N3 S) in the ground state has been calculated using the Hartree-Fock and density functional method (B3LYP) with 6-31G(d) basis set. The optimized geometric bond lengths and bond angles obtained by using HF and DFT (B3LYP) show the best agreement with the experimental data. Comparison of the observed fundamental vibrational frequencies of 2-amino-5-phenyl-1,3,4-thiadiazole (C8 H7 N3 S) and calculated results by density functional B3LYP and Hartree-Fock methods indicate that B3LYP is superior to the scaled Hartree-Fock approach for molecular vibrational problems. © 2005 Elsevier B.V. All rights reserved. Keywords: 2-Amino-5-phenyl-1,3,4-thiadiazole; IR spectra; DFT; HF; Vibrational assignment; Crystal structure
1. Introduction The 2-amino-5-phenyl-1,3,4-thiadiazole ring is associated with diverse biological activities, which can be explained by the presence of the toxiphocic N C S linkage, the importance of which in many pesticides has been reported [1–3]. Various 2-amino-substituted 1,3,4-thiadiazolles and their Schiff bases also exhibit diverse biological and pharmacological activities [4–9]. Density functional theory calculations are reported to provide excellent vibrational frequencies of organic compounds if the calculated frequencies are scaled to compensate for the approximate treatment of electron correlation, for basis set deficiencies and for the anharmonicity [10,11]. Rauhaut and Pulay calculated the vibrational spectra of 31 molecules by using B3LYP method with 6-31G(d) basis set [12]. In their work, they calculated vibrational frequencies of 20 smaller molecules whose experimental vibrational frequencies are well assigned, and derived transferable scaling factors
by using least-square method. The scaling factors are successfully applied to other eleven larger molecules. Thus, vibrational frequencies calculated by using the B3LYP functional with 6-31G(d) basis could be utilized to eliminate the uncertainties in the fundamental assignments in infrared and Raman vibrational spectra [13]. In previous publication, the crystal structure and vibrational spectra of the title compound had been studied [14]. However, as far as we know, there are no theoretical results for the title compound (C8 H7 N3 S) in the literature. In this work, we have calculated the vibrational frequencies of the title compound (C8 H7 N3 S) in the ground state to distinguish the fundamentals from the experimental vibrational frequencies and geometric parameters, by using the HF and DFT (B3LYP) method. These calculations are valuable for providing insight into the vibrational spectrum and molecular parameters.
2. Calculations ∗
Corresponding author. Tel.: +90 424 23700006591; fax: +90 424 2330062. E-mail address: [email protected] (F. Yakuphanoglu). 1386-1425/$ – see front matter © 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.saa.2005.06.038
The molecular structures of the title compound (C8 H7 N3 S) in the ground state (in vacuo) are optimized by
Y. Atalay et al. / Spectrochimica Acta Part A 64 (2006) 68–72
HF and B3LYP with the 6-31G(d) basis set. Two sets of vibrational frequencies for these species are calculated with these methods and then scaled by 0.8929 and 0.9613, respectively. Molecular geometry is restricted and all the calculations are performed by using Gauss-View molecular visualisation program [15] and Gaussian 98 program package on personal computer [16].
3. Results and discussion The features of molecular geometry and vibrational of spectra of 2-amino-5-phenyl-1,3,4-thiadiazole have been characterized [14]. It geometric structure is monoclinic, ˚ space group P21/C , with the cell dimensions a = 10.604 A, ◦ ˚ ˚ b = 7.922 A, c = 11.116 A, α = β = 117.965 , and V = 824.8 A3 [14]. We have shown theoretical and experimental crystal structure of the title compound (C8 H7 N3 S) in Fig. 1. The optimized geometric parameters (bond lengths and angles) by HF and B3LYP with 6-31G(d) as the basic set are listed in Table 1 and compared with the experimental crystal geometry for the title compound (C8 H7 N3 S). For the optimized
69
Table 1 Optimized and experimental geometries of the title compound in the ground state Parameters
Experimentala
Calculated (6-31G(d)) HF
˚ Bond lengths (A) S(16) C(15) S(16) C(9) N(17) C(15) N(13) N(14) N(14) C(15) N(13) C(9) Bond angles (◦ ) C(15) S(16) C(9) N(13) N(14) C(15) N(14) N(13) C(9) N(17) C(15) N(14) S(16) C(15) N(14) S(16) C(15) N(17) S(16) C(9) N(13) S(16) C(9) C(3) N(13) C(9) C(3)
1.749(2) 1.751(18) 1.337(2) 1.384(2) 1.320(2) 1.300(2) 87.01(7) 112.21(13) 113.94(12) 124.42(5) 113.55(11) 122.04(12) 113.30(11) 122.48(12) 124.18(13)
1.740 1.758 1.371 1.364 1.274 1.269 86.0 112.6 114.7 123.8 114.1 121.9 112.5 123.5 123.9
B3LYP 1.759 1.782 1.375 1.364 1.348 1.352 87.8 112.5 114.5 123.8 114.0 122.1 112.5 123.6 124.2
Bond lengths in angstrom, and bond angles in degrees. a Taken from reference [14].
Fig. 1. (a) The experimental geometric structure of the title compound (displacement ellipsoids for non-H atoms are drawn at the 50% probability level) taken from reference [14]; (b) the theoretical geometric structure of the title compound.
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Fig. 2. (a) Correlation graphics of calculated and experimental molecular bond lengths of the title compound; (b) correlation graphics of calculated and experimental molecular bond angles of the title compound.
geometric parameters, various methods including HF method estimates some bond lengths well to some extent [17–20]. We noted that the experimental results belong to solid phase and theoretical calculations belong to gaseous phase. The correlation between the experimental and calculated geometric parameters obtained by the several methods is shown in Fig. 2. Owing to our calculations, HF method correlates well for the bond length compare with the other method (Table 1, Fig. 2). The largest difference between experimental and calculated ˚ (Angstrom). The B3LYP HF bond length is about 0.046 A method leads to geometric parameters, which are much closer to experimental data. This pattern was not found for bond length, as can be seen from Table 1, whereas in the case of B3LYP method, the biggest difference between calculated and experimental values of bond lengths was reached to be ˚ 0.052 A. The bond angles provided by B3LYP method is the closest the experimental values (Table 1). The largest difference is about 1.5◦ for the second one. As a result, the optimized bond lengths obtained by HF method and bond angles by DFT (B3LYP) method show the best agreement with the experimental values. We have not found theoretical results for the title compound (C8 H7 N3 O) in the literature and experimental vibrational spectra of the title compound (C8 H7 N3 O) have been
taken by Ref. [14]. We have calculated the theoretical vibrational spectra of the title compound (C8 H7 N3 O) using B3LYP and HF method with 6-31G(d) basis set. We have compared our calculation of the title compound (C8 H7 N3 O) with their experimental results. Theoretical and experimental results of the title compound (C8 H7 N3 O) are shown in Table 2. The vibrational bands’ assignments have been made by using Gauss-View molecular visualization program [15]. To make comparison with experiment, we present correlation graphic in Fig. 3 based on the calculations. As we can see from correlation graphic in Fig. 3 experimental fundamentals are in better agreement with the scaled fundamentals and are found to have a good correlation for B3LYP than HF. As can be seen from Table 2, the NH2 asymmetric and symmetric vibrations of (C8 H7 N3 O) have been calculated by using HF and B3LYP method with 6-31G(d) basis set at 3478–3517 cm−1 (asymmetric) and 3381–3413 cm−1 (symmetric), respectively; but experimental NH2 asymmetric and symmetric vibrations have been observed at 3515–3407 cm−1 [14]. The C H experimental and theoretical vibrational bands of the title compound (C8 H7 N3 O) have been shown in Table 2, there is a good agreement between experimental and theoretical values. The S C stretch vibration was observed at 1235 cm−1 , in this study that have calculated at 1241 cm−1 (HF) and at 1234 cm−1 (B3LYP). As can be seen from Table 2, there is
Y. Atalay et al. / Spectrochimica Acta Part A 64 (2006) 68–72
71
Table 2 Comparison of the observed and calculated vibrational spectra of the title compound Assignments
Experimentala (IR with KBr)
Calculated (6-31G(d) HF
B3LYP Intensity
NH2 asym. str. NH2 sym. str. C H str. C H str. C H asym. str. CH asym. str. CH asym. str. CH2 sci. C C str. C C str. C C str. C N str. C N str., C H rock. C H rock. C H rock. N H rock. N H rock., C H rock. S C str. C H bend. N N str. Ring twist. NH2 twist., N N str. Ring twist. N C S bend. Ring wag. C N N bend. Ring out of plane bend. Ring out of plane bend. Ring bend. Ring tor. N C S C wag., ring wag. C S C sci. NH2 twist. Ring wag., NH2 twist. NH2 rock. N H wag. NH2 wag. NH2 tor. a
3515 3407 3111 3078 3073 3064 3059 1630 1601 1569 1494 1489 1465 1428 1324 1301 1291 1235 1169 1131 1071 1028 1023 948 887 755 750 676 647 609 586 576 544 474 404 – – –
3498 3391 3138 3027 3017 3026 2999 1628 1596 1564 1545 1490 1439 – 1316 – – 1241 1167 1155 – 1054 974 955 937 756 – 683 661 606 581 561 – 485 411 352 – 262
0.16 0.25 0.01 0.1 0.13 0.03 0.02 0.82 0.01 0.08 0.86 0.08 0.05 – 001 – – 0.14 0.01 0.11 – 0.01 0.15 0.04 0.31 0.04 – 0.04 0.02 0.02 0.39 0.09 – 0.05 0.03 0.22 – 0.01
Taken from reference [14].
Fig. 3. Correlation graphics of calculated and experimental frequencies of the title compound.
Intensity 3517 3413 3107 3088 3076 3066 3059 1606 1597 1573 1495 1488 1464 1431 1318 1301 1289 1234 1169 1129 1074 1030 1020 947 894 755 748 676 661 608 587 571 543 477 410 339 325 282
0.1 0.2 0.01 0.08 0.09 0.01 0.03 0.58 0.01 0.01 0.02 1.0 0.05 0.01 0.02 0.15 0.05 0.16 0.01 0.04 0.01 0.14 0.01 0.12 0.01 0.01 0.1 0.08 0.17 0.01 0.02 0.01 0.47 0.12 0.01 0.05 0.01 0.15
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a good agreement between experimental and the theoretical vibration values. 4. Conclusions In this work, we have calculated the geometric parameters and vibrational frequencies of the title compound (C8 H7 N3 O) by using B3LYP and HF method with 6-31G(d) basis set. To fit the theoretical results with experimental ones for B3LYP we have multiplied by 0.9613, whereas for HF method the number of 0.8929 was used with these. Multiplication factors results gained seemed to be in a good agreement with experimental ones. In particular, the results of B3LYP method has shown better fit to experimental ones than HF in evaluating vibrational frequencies. But, B3LYP method seems to be appropriate than HF method for the calculation of geometrical parameters of molecules. References [1] A.E. Abdel-Rahman, A. Mahmoud, H.A. El-Sherief, A.G. Gahatta, Chem. Abstr. 98 (1983) 72012b. [2] H. Foerster, V. Mues, B. Baasner, H. Hagemann, I. Eue, R. Schmidt, Eur. Patent No. 60426 (1981). [3] N. Tiwari, B. Chatuverdi, A. Nizamuddin, Indian J. Chem. B 28 (1989) 200–212. [4] H. Singh, L.D. Yadav, Agric. Biol. Chem. 40 (1976) 759–767. [5] F. Russo, M.J. Santagari, J. Heterocycl. Chem. 22 (1985) 297–304. [6] S. Masahito, M. Kazuyuki, Agric. Biol. Chem. 41 (1977) 2047–2053.
[7] T. Ramalingam, M. Sre Rama Murty, P.B. Suttur, Heterocycles 29 (1989) 925–932. [8] B. Ludwing, H. Dietrich, H. Horts, J. Guenter, K. Gerard, R. Tilo, E. Thomas, T. Ernst, Ger. Patent DD 24/003 (1987) (CIC07D513/04, June). ¨ urk, M. Akkurt, A. Cansız, M. Koparır, M. S¸ekerci, F.W. [9] S. Ozt¨ Heinemann, Acta Cryst. E 60 (2004) 425–427. [10] Yu.A. Abramov, A. Volkov, P. Coppens, Chem. Phys. Lett. 311 (1999) 81–86. [11] N.C. Handy, P.E. Maslen, R.D. Amons, J.S. Audrows, C.W. Murroy, G. Lawing, Chem. Phys. Lett. 197 (1992) 506. [12] S.Y. Lee, B.H. Boo, Bull. Korean Chem. Soc. 17 (1996) 760. [13] G. Rauhaut, P. Pulay, J. Phys. Chem. 99 (1995) 3093. ¨ urk, M. Akkurt, A. Cansız, M. Koparır, M. S¸ekerci, F.W. [14] S. Ozt¨ Heinemann, Acta Cryst. E 60 (2004) o820–o821. [15] A. Frish, A.B. Nielsen, A.J. Holder, Gaussview User Manual, Gaussian Inc, Pittsburg, 2001. [16] M.J. Frisch, G.W. Trucks, H.B. Schlegel, G.E. Scuseria, M.A. Robb, J.R. Cheeseman, V.G. Zakrzewski, J.A. Montgomery Jr., R.E. Stratmann, J.C. Burant, S. Dapprich, J.M. Millam, A.D. Daniels, K.N. Kudin, M.C. Strain, O. Farkas, J. Tomasi, V. Barone, M. Cossi, R. Cammi, B. Mennucci, C. Pomelli, C. Adamo, S. Clifford, J. Ochterski, G.A. Petersson, P.Y. Ayala, Q. Cui, K. Morokuma, P. Salvador, J.J. Dannenberg, D.K. Malick, A.D. Rabuck, K. Raghavachari, J.B. Foresman, J. Cioslowski, J.V. Ortiz, A.G. Baboul, B.B. Stefanov, G. Liu, A. Liashenko, P. Piskorz, I. Komaromi, R. Gomperts, R.L. Martin, D.J. Fox, T. Keith, M.A. Al-Laham, C.Y. Peng, A. Nanayakkara, M. Challacombe, P.M.W. Gill, W. Johnson, M.W. Chen, J.L. Wong, C. Andres, M. Gonzalez, E.S. Head-Gordon, J.A. Replogle, Pople, Gaussian 98, Revision A.9, Gaussian Inc, Pittsburgh, PA, 2001. [17] S.Y. Lee, Bull. Korean Chem. Soc. 19 (1) (1998) 93. [18] C.J.M. Wheeless, X. Zou, R. Liu, J. Phys. Chem. 99 (1995) 1248. [19] S.Y. Lee, B.H. Boo, J. Phys. Chem. 100 (1996) 15073. [20] Y. Atalay, D. Avcı, A. Bas¸o˘glu, ˙I. Okur, J. Mol. Struct. Theochem. 713 (2005) 21–26.
Theoretical studies of molecular structure and vibrational spectra of 2-amino-5-phenyl-1,3,4-thiadiazole Y. Atalay a , F. Yakuphanoglu b,∗ , M. Sekerci c , D. Avcı a , A. Bas¸o˘glu a a
Sakarya University, Faculty of Arts and Sciences, Department of Physics, Sakarya, Turkey b Firat University, Faculty of Arts and Sciences, Department of Physics, Elazig, Turkey c Firat University, Faculty of Arts and Sciences, Department of Chemistry, Elazig, Turkey Received 8 June 2005; accepted 29 June 2005
Abstract The molecular geometry and vibrational frequencies of 2-amino-5-phenyl-1,3,4-thiadiazole (C8 H7 N3 S) in the ground state has been calculated using the Hartree-Fock and density functional method (B3LYP) with 6-31G(d) basis set. The optimized geometric bond lengths and bond angles obtained by using HF and DFT (B3LYP) show the best agreement with the experimental data. Comparison of the observed fundamental vibrational frequencies of 2-amino-5-phenyl-1,3,4-thiadiazole (C8 H7 N3 S) and calculated results by density functional B3LYP and Hartree-Fock methods indicate that B3LYP is superior to the scaled Hartree-Fock approach for molecular vibrational problems. © 2005 Elsevier B.V. All rights reserved. Keywords: 2-Amino-5-phenyl-1,3,4-thiadiazole; IR spectra; DFT; HF; Vibrational assignment; Crystal structure
1. Introduction The 2-amino-5-phenyl-1,3,4-thiadiazole ring is associated with diverse biological activities, which can be explained by the presence of the toxiphocic N C S linkage, the importance of which in many pesticides has been reported [1–3]. Various 2-amino-substituted 1,3,4-thiadiazolles and their Schiff bases also exhibit diverse biological and pharmacological activities [4–9]. Density functional theory calculations are reported to provide excellent vibrational frequencies of organic compounds if the calculated frequencies are scaled to compensate for the approximate treatment of electron correlation, for basis set deficiencies and for the anharmonicity [10,11]. Rauhaut and Pulay calculated the vibrational spectra of 31 molecules by using B3LYP method with 6-31G(d) basis set [12]. In their work, they calculated vibrational frequencies of 20 smaller molecules whose experimental vibrational frequencies are well assigned, and derived transferable scaling factors
by using least-square method. The scaling factors are successfully applied to other eleven larger molecules. Thus, vibrational frequencies calculated by using the B3LYP functional with 6-31G(d) basis could be utilized to eliminate the uncertainties in the fundamental assignments in infrared and Raman vibrational spectra [13]. In previous publication, the crystal structure and vibrational spectra of the title compound had been studied [14]. However, as far as we know, there are no theoretical results for the title compound (C8 H7 N3 S) in the literature. In this work, we have calculated the vibrational frequencies of the title compound (C8 H7 N3 S) in the ground state to distinguish the fundamentals from the experimental vibrational frequencies and geometric parameters, by using the HF and DFT (B3LYP) method. These calculations are valuable for providing insight into the vibrational spectrum and molecular parameters.
2. Calculations ∗
Corresponding author. Tel.: +90 424 23700006591; fax: +90 424 2330062. E-mail address: [email protected] (F. Yakuphanoglu). 1386-1425/$ – see front matter © 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.saa.2005.06.038
The molecular structures of the title compound (C8 H7 N3 S) in the ground state (in vacuo) are optimized by
Y. Atalay et al. / Spectrochimica Acta Part A 64 (2006) 68–72
HF and B3LYP with the 6-31G(d) basis set. Two sets of vibrational frequencies for these species are calculated with these methods and then scaled by 0.8929 and 0.9613, respectively. Molecular geometry is restricted and all the calculations are performed by using Gauss-View molecular visualisation program [15] and Gaussian 98 program package on personal computer [16].
3. Results and discussion The features of molecular geometry and vibrational of spectra of 2-amino-5-phenyl-1,3,4-thiadiazole have been characterized [14]. It geometric structure is monoclinic, ˚ space group P21/C , with the cell dimensions a = 10.604 A, ◦ ˚ ˚ b = 7.922 A, c = 11.116 A, α = β = 117.965 , and V = 824.8 A3 [14]. We have shown theoretical and experimental crystal structure of the title compound (C8 H7 N3 S) in Fig. 1. The optimized geometric parameters (bond lengths and angles) by HF and B3LYP with 6-31G(d) as the basic set are listed in Table 1 and compared with the experimental crystal geometry for the title compound (C8 H7 N3 S). For the optimized
69
Table 1 Optimized and experimental geometries of the title compound in the ground state Parameters
Experimentala
Calculated (6-31G(d)) HF
˚ Bond lengths (A) S(16) C(15) S(16) C(9) N(17) C(15) N(13) N(14) N(14) C(15) N(13) C(9) Bond angles (◦ ) C(15) S(16) C(9) N(13) N(14) C(15) N(14) N(13) C(9) N(17) C(15) N(14) S(16) C(15) N(14) S(16) C(15) N(17) S(16) C(9) N(13) S(16) C(9) C(3) N(13) C(9) C(3)
1.749(2) 1.751(18) 1.337(2) 1.384(2) 1.320(2) 1.300(2) 87.01(7) 112.21(13) 113.94(12) 124.42(5) 113.55(11) 122.04(12) 113.30(11) 122.48(12) 124.18(13)
1.740 1.758 1.371 1.364 1.274 1.269 86.0 112.6 114.7 123.8 114.1 121.9 112.5 123.5 123.9
B3LYP 1.759 1.782 1.375 1.364 1.348 1.352 87.8 112.5 114.5 123.8 114.0 122.1 112.5 123.6 124.2
Bond lengths in angstrom, and bond angles in degrees. a Taken from reference [14].
Fig. 1. (a) The experimental geometric structure of the title compound (displacement ellipsoids for non-H atoms are drawn at the 50% probability level) taken from reference [14]; (b) the theoretical geometric structure of the title compound.
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Fig. 2. (a) Correlation graphics of calculated and experimental molecular bond lengths of the title compound; (b) correlation graphics of calculated and experimental molecular bond angles of the title compound.
geometric parameters, various methods including HF method estimates some bond lengths well to some extent [17–20]. We noted that the experimental results belong to solid phase and theoretical calculations belong to gaseous phase. The correlation between the experimental and calculated geometric parameters obtained by the several methods is shown in Fig. 2. Owing to our calculations, HF method correlates well for the bond length compare with the other method (Table 1, Fig. 2). The largest difference between experimental and calculated ˚ (Angstrom). The B3LYP HF bond length is about 0.046 A method leads to geometric parameters, which are much closer to experimental data. This pattern was not found for bond length, as can be seen from Table 1, whereas in the case of B3LYP method, the biggest difference between calculated and experimental values of bond lengths was reached to be ˚ 0.052 A. The bond angles provided by B3LYP method is the closest the experimental values (Table 1). The largest difference is about 1.5◦ for the second one. As a result, the optimized bond lengths obtained by HF method and bond angles by DFT (B3LYP) method show the best agreement with the experimental values. We have not found theoretical results for the title compound (C8 H7 N3 O) in the literature and experimental vibrational spectra of the title compound (C8 H7 N3 O) have been
taken by Ref. [14]. We have calculated the theoretical vibrational spectra of the title compound (C8 H7 N3 O) using B3LYP and HF method with 6-31G(d) basis set. We have compared our calculation of the title compound (C8 H7 N3 O) with their experimental results. Theoretical and experimental results of the title compound (C8 H7 N3 O) are shown in Table 2. The vibrational bands’ assignments have been made by using Gauss-View molecular visualization program [15]. To make comparison with experiment, we present correlation graphic in Fig. 3 based on the calculations. As we can see from correlation graphic in Fig. 3 experimental fundamentals are in better agreement with the scaled fundamentals and are found to have a good correlation for B3LYP than HF. As can be seen from Table 2, the NH2 asymmetric and symmetric vibrations of (C8 H7 N3 O) have been calculated by using HF and B3LYP method with 6-31G(d) basis set at 3478–3517 cm−1 (asymmetric) and 3381–3413 cm−1 (symmetric), respectively; but experimental NH2 asymmetric and symmetric vibrations have been observed at 3515–3407 cm−1 [14]. The C H experimental and theoretical vibrational bands of the title compound (C8 H7 N3 O) have been shown in Table 2, there is a good agreement between experimental and theoretical values. The S C stretch vibration was observed at 1235 cm−1 , in this study that have calculated at 1241 cm−1 (HF) and at 1234 cm−1 (B3LYP). As can be seen from Table 2, there is
Y. Atalay et al. / Spectrochimica Acta Part A 64 (2006) 68–72
71
Table 2 Comparison of the observed and calculated vibrational spectra of the title compound Assignments
Experimentala (IR with KBr)
Calculated (6-31G(d) HF
B3LYP Intensity
NH2 asym. str. NH2 sym. str. C H str. C H str. C H asym. str. CH asym. str. CH asym. str. CH2 sci. C C str. C C str. C C str. C N str. C N str., C H rock. C H rock. C H rock. N H rock. N H rock., C H rock. S C str. C H bend. N N str. Ring twist. NH2 twist., N N str. Ring twist. N C S bend. Ring wag. C N N bend. Ring out of plane bend. Ring out of plane bend. Ring bend. Ring tor. N C S C wag., ring wag. C S C sci. NH2 twist. Ring wag., NH2 twist. NH2 rock. N H wag. NH2 wag. NH2 tor. a
3515 3407 3111 3078 3073 3064 3059 1630 1601 1569 1494 1489 1465 1428 1324 1301 1291 1235 1169 1131 1071 1028 1023 948 887 755 750 676 647 609 586 576 544 474 404 – – –
3498 3391 3138 3027 3017 3026 2999 1628 1596 1564 1545 1490 1439 – 1316 – – 1241 1167 1155 – 1054 974 955 937 756 – 683 661 606 581 561 – 485 411 352 – 262
0.16 0.25 0.01 0.1 0.13 0.03 0.02 0.82 0.01 0.08 0.86 0.08 0.05 – 001 – – 0.14 0.01 0.11 – 0.01 0.15 0.04 0.31 0.04 – 0.04 0.02 0.02 0.39 0.09 – 0.05 0.03 0.22 – 0.01
Taken from reference [14].
Fig. 3. Correlation graphics of calculated and experimental frequencies of the title compound.
Intensity 3517 3413 3107 3088 3076 3066 3059 1606 1597 1573 1495 1488 1464 1431 1318 1301 1289 1234 1169 1129 1074 1030 1020 947 894 755 748 676 661 608 587 571 543 477 410 339 325 282
0.1 0.2 0.01 0.08 0.09 0.01 0.03 0.58 0.01 0.01 0.02 1.0 0.05 0.01 0.02 0.15 0.05 0.16 0.01 0.04 0.01 0.14 0.01 0.12 0.01 0.01 0.1 0.08 0.17 0.01 0.02 0.01 0.47 0.12 0.01 0.05 0.01 0.15
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a good agreement between experimental and the theoretical vibration values. 4. Conclusions In this work, we have calculated the geometric parameters and vibrational frequencies of the title compound (C8 H7 N3 O) by using B3LYP and HF method with 6-31G(d) basis set. To fit the theoretical results with experimental ones for B3LYP we have multiplied by 0.9613, whereas for HF method the number of 0.8929 was used with these. Multiplication factors results gained seemed to be in a good agreement with experimental ones. In particular, the results of B3LYP method has shown better fit to experimental ones than HF in evaluating vibrational frequencies. But, B3LYP method seems to be appropriate than HF method for the calculation of geometrical parameters of molecules. References [1] A.E. Abdel-Rahman, A. Mahmoud, H.A. El-Sherief, A.G. Gahatta, Chem. Abstr. 98 (1983) 72012b. [2] H. Foerster, V. Mues, B. Baasner, H. Hagemann, I. Eue, R. Schmidt, Eur. Patent No. 60426 (1981). [3] N. Tiwari, B. Chatuverdi, A. Nizamuddin, Indian J. Chem. B 28 (1989) 200–212. [4] H. Singh, L.D. Yadav, Agric. Biol. Chem. 40 (1976) 759–767. [5] F. Russo, M.J. Santagari, J. Heterocycl. Chem. 22 (1985) 297–304. [6] S. Masahito, M. Kazuyuki, Agric. Biol. Chem. 41 (1977) 2047–2053.
[7] T. Ramalingam, M. Sre Rama Murty, P.B. Suttur, Heterocycles 29 (1989) 925–932. [8] B. Ludwing, H. Dietrich, H. Horts, J. Guenter, K. Gerard, R. Tilo, E. Thomas, T. Ernst, Ger. Patent DD 24/003 (1987) (CIC07D513/04, June). ¨ urk, M. Akkurt, A. Cansız, M. Koparır, M. S¸ekerci, F.W. [9] S. Ozt¨ Heinemann, Acta Cryst. E 60 (2004) 425–427. [10] Yu.A. Abramov, A. Volkov, P. Coppens, Chem. Phys. Lett. 311 (1999) 81–86. [11] N.C. Handy, P.E. Maslen, R.D. Amons, J.S. Audrows, C.W. Murroy, G. Lawing, Chem. Phys. Lett. 197 (1992) 506. [12] S.Y. Lee, B.H. Boo, Bull. Korean Chem. Soc. 17 (1996) 760. [13] G. Rauhaut, P. Pulay, J. Phys. Chem. 99 (1995) 3093. ¨ urk, M. Akkurt, A. Cansız, M. Koparır, M. S¸ekerci, F.W. [14] S. Ozt¨ Heinemann, Acta Cryst. E 60 (2004) o820–o821. [15] A. Frish, A.B. Nielsen, A.J. Holder, Gaussview User Manual, Gaussian Inc, Pittsburg, 2001. [16] M.J. Frisch, G.W. Trucks, H.B. Schlegel, G.E. Scuseria, M.A. Robb, J.R. Cheeseman, V.G. Zakrzewski, J.A. Montgomery Jr., R.E. Stratmann, J.C. Burant, S. Dapprich, J.M. Millam, A.D. Daniels, K.N. Kudin, M.C. Strain, O. Farkas, J. Tomasi, V. Barone, M. Cossi, R. Cammi, B. Mennucci, C. Pomelli, C. Adamo, S. Clifford, J. Ochterski, G.A. Petersson, P.Y. Ayala, Q. Cui, K. Morokuma, P. Salvador, J.J. Dannenberg, D.K. Malick, A.D. Rabuck, K. Raghavachari, J.B. Foresman, J. Cioslowski, J.V. Ortiz, A.G. Baboul, B.B. Stefanov, G. Liu, A. Liashenko, P. Piskorz, I. Komaromi, R. Gomperts, R.L. Martin, D.J. Fox, T. Keith, M.A. Al-Laham, C.Y. Peng, A. Nanayakkara, M. Challacombe, P.M.W. Gill, W. Johnson, M.W. Chen, J.L. Wong, C. Andres, M. Gonzalez, E.S. Head-Gordon, J.A. Replogle, Pople, Gaussian 98, Revision A.9, Gaussian Inc, Pittsburgh, PA, 2001. [17] S.Y. Lee, Bull. Korean Chem. Soc. 19 (1) (1998) 93. [18] C.J.M. Wheeless, X. Zou, R. Liu, J. Phys. Chem. 99 (1995) 1248. [19] S.Y. Lee, B.H. Boo, J. Phys. Chem. 100 (1996) 15073. [20] Y. Atalay, D. Avcı, A. Bas¸o˘glu, ˙I. Okur, J. Mol. Struct. Theochem. 713 (2005) 21–26.