Microsoft Word - Joshi(113-121) Bhawani D. Joshi, Manoj K. Chaudhary/ BIBECHANA 15 (2018) 131-139: RCOST p.131 BIBECHANA A Multidisciplinary Journal of Science, Technology and Mathematics ISSN 2091-0762 (Print), 2382-5340 (0nline) Journal homepage: http://nepjol.info/index.php/BIBECHANA Publisher: Research Council of Science and Technology, Biratnagar, Nepal NBO, nonlinear optical and thermodynamic properties of 10-Acetyl-10H-phenothiazine 5-oxide Bhawani Datt Joshi1,2*, Manoj Kumar Chaudhary3 1Department of Physics, Siddhanath Sc. Campus, Tribhuvan University, Nepal 2Departamento de Física, Universidade Federal do Ceará, Fortaleza, CE, Brazil. 3Department of Physics, Amrit Sc. Campus, Tribhuvan University, Nepal *Email: pbdjoshi@gmail.com Article history: Received 11 October, 2017; 11 December, 2017 DOI: http://dx.doi.org/10.3126/bibechana.v15i0.18385 This work is licensed under the Creative Commons CC BY-NC License. https://creativecommons.org/licenses/by-nc/4.0/ Abstract In this paper, natural bond orbital (NBO) analysis, nonlinear optical and the thermodynamic properties of 10-Acetyl-10H-phenothiazine 5-oxide have been analyzed by employing density functional theory level employing 6-311++G(d,p) basis set. NBO analysis reveals that the intra- intermolecular charge transfer occurs within the molecule leading to the stabilization. The predicted nonlinear optical properties (NLO) like; polarizability and first hyperpolarizabiliy support that the molecule could attract the interests for future investigation. Keywords: APTZ; DFT; NBO, Nonlinear optical and thermodynamic properties. 1. Introduction The heterocyclic organic compounds in which sulphur and nitrogen are incorporated in the tricyclic system; exhibit a wide range of pharmacological / biological activities [1-5]. Different derivatives of phnothiozene are kwon for their clinical activities. Antihistamines, diuretics, analgesics, neurolepitcs, antileukemic, antimutagenic, antileishmanial etc. are some of their main potential applications [2-7] of the drugs that containing phenothiozenes. Pallafox et. al. [6] studied the infrared, Raman and 13C-NMR spectroscopic studies of N-Methyl Phenothiazine. Sharma et. al. [7] reported various remarkable biological activities of thiazolidines. Previously, we have revealed vibrational analysis of 10-Acetyl-10H-phenothiazine5-oxide [APTZ] using quantum chemical calculations [8]. The aim of the present study is to communicate some additional investigations on structure activity relation of the molecule on the APTZ molecule. In this study, we have presented the nonlinear optical and thermodynamic properties together with the natural bond orbital (NBO) analysis of the title compound by employing density functional theory [DFT] [9] 6-311++G(d,p) basis set [10] using Gaussian 09 program package [11]. 2. Materials and methods 2.1. Theoretical method Using the data available in PubChem data base [12] geometry optimization has been performed Bhawani D. Joshi, Manoj K. Chaudhary/ BIBECHANA 15 (2018) 131-139: RCOST p.132 without using any constraints. The optimized ground state structure of the molecule obtained by DFT method visualized in Gauss View program [13] is shown in Figure 1. We have utilized the DFT based on Becke’s three-parameter (local, non-local, HF) hybrid exchange functional with Lee–Yang–Parr correlation functional (B3LYP) [10]. Fig. 1: Optimized structure of APTZ molecule (sulphur: yellow, nitrogen: blue, oxygen: red, carbon: gray and hydrogen: white in colours). The basis set 6-311++G(d,p) augmented by ‘d’ polarization functions on heavy atoms (nitrogen, sulphur etc.) and ‘p’ polarization functions on hydrogen atoms as well as diffuse functions for both hydrogen and heavy atoms. 3. Results and Discussion 3.1. Natural bond orbital (NBO) analysis NBO analysis is one of the efficient methods for studying hybridization, conjugative interactions, covalence effects and charge transfer in polyatomic wave functions into localized form, corresponding to one center (lone pairs) and two centers (bonds) of Lewis structure picture [14]. Here, by utilizing the second-order micro-disturbance theory analysis we have reported some of the electron donor orbital, acceptor orbital and the interacting stabilization energy. The intensity of the interaction between electron donors and electron acceptors, i.e. the more donating tendency from electron donors to electron acceptors depends on the E(2) value. The hyperconjugative interaction energy was deduced from the second-order perturbation approach [15, 16]. E��� � �n� σ|F|σ�� E�∗ � E�⁄ � � �n��F��� ∆E⁄ � whereF��� is the Fock matrix element between i and j NBO orbital, E�and E�∗are the energies of �and �*NBO’s, and n� is the population of the donor orbital. The larger the E(2) value the more intensive is interaction between electron donors and electron acceptors , the greater the extent of conjugation of the whole system [14]. Hyperconjugation is a stabilizing effect that arises from overlap between an occupied orbital with another neighboring electron deficient orbital when these orbitals are properly oriented. The most important interaction between ‘‘filled’’ (donor) Lewis type NBOs and ‘‘empty’’ (acceptor) non-Lewis NBOs are reported in Table 1. A strong intramolecular hyperconjugative interaction of � electrons occurs from C1-C10 to the �*(C2 – C4) and �*(C6 – C8) bonds of the ring R1 which increase the electron densities (EDs) (0.31e and 0.32e) leading to the stabilizations of 20.07 and 16.82 kcal/mol, respectively. Another intermolecular Bhawani D. Joshi, Manoj K. Chaudhary/ BIBECHANA 15 (2018) 131-139: RCOST p.133 hyperconjugative interaction of � electrons occurs from C17-C19 to the �*(C11 – C12) and �*(C13 – C15) bonds of the ring R3 which increase the EDs (0.43e and 0.31e) leading to the stabilizations 23.89 kcal/mol and 18.92 kcal/mol, respectively. The enhanced interaction Table 1. Second order perturbation theory analysis of Fock matrix in NBO Basis. Donor NBO (i) ED/e Acceptor NBO (j) ED/e E(2) kcal/mol E(j)-E(i) a.u. F(i,j)a.u. �(C13-H14) 1.97771 �*(C11-C12) 0.03212 5.08 1.06 0.065 �(C19-H20) 1.97695 �*(C11-C12) 0.03212 5.03 1.05 40.065 �*(S28-O29) 0.13706 �*(S28-O30) 0.15311 58.58 0.01 0.069 π(C1-C10) 1.67702 π*(C2-C4) 0.30670 20.07 0.30 0.070 π*(C6-C8) 0.32028 16.82 0.30 0.063 π(C2-C4) 1.64157 π*(C1-C10) 0.43019 20.47 0.26 0.067 π*(C6-C8) 0.32028 21.67 0.28 0.070 π(C6-C8) 1.65806 π*(C1-C10) 0.43019 23.09 0.27 0.072 π*(C2-C4) 0.30670 18.10 0.29 0.065 π(C11-C12) 1.68646 π*(C13-C15) 0.30962 20.12 0.30 0.070 π*(C17-C19) 0.30712 16.33 0.31 0.063 π(C13-C15) 1.64879 π*(C11-C12) 0.43279 20.21 0.26 0.066 π*(C17-C19) 0.30712 20.51 0.29 0.069 π(C17-C19) 1.64130 π*(C11-C12) 0.43279 23.89 0.26 0.072 π*(C13-C15) 0.30962 18.92 0.28 0.066 LP(1)N26 1.68652 π*(C1-C10) 0.43019 14.67 0.27 0.058 π*(C11-C12) 0.43279 14.63 0.27 0.058 π*(C21-O27) 0.01587 41.57 0.30 0.102 LP(2)O27 1.85623 �*(C21-C22) 0.05125 18.85 0.62 0.099 �*(C21-N26) 0.10121 30.04 0.64 0.126 LP(2)O29 1.80719 �*(C1-S28) 0.20940 12.01 0.45 0.066 �*(C12-S28) 0.20601 17.58 0.45 0.079 LP(3)O29 1.79804 �*(S28-O30) 0.15311 21.15 0.57 0.100 LP(2)O30 1.81031 �*(C1-S28) 0.20940 14.23 0.44 0.071 �*(C12-S28) 0.20601 14.70 0.44 0.072 LP(3)O30 1.77862 �*(S28-O29) 0.13706 21.63 0.55 0.100 π*(C1-C10) 0.43019 π*(C2-C4) 0.30670 149.22 0.02 0.081 π*(C6-C8) 0.32028 195.11 0.02 0.083 π*(C11-C12) 0.43279 π*(C13-C15) 0.30962 138.07 0.02 0.080 π*(C17-C19) 0.30712 135.91 0.02 0.084 E(2) means energy of hyper conjugative interaction (stabilization energy). E(i)-E(j) is the energy difference between donor (i) and acceptor ( j) NBO orbitals. F(i,j) is the Fock matrix element between i and j NBO orbitals. π*(C1-C10) further conjugate with the NBOs π*(C2-C4) and π*(C6-C8) resulting to high stabilizations 149.22 and 195.11 kcal/mol. Similarly, the enhanced interaction π*(C11-C12) further conjugates with the NBOs π*(C13-C15) and π*(C17-C19) leading to the high stabilizations 138.07 and 135.91 kcal/mole, respectively. Further, the other significant hyperconjugative interactions of π electrons in the molecular system are from π(C2-C4) to π*(C1-C10) / π*(C6-C8) leading energies 20.47 / 21.67 kcal/mol, and from π(C13-C15) to π*(C11-C12) /π*(C17-C19) leading energies 20.21 / 20.51 kcal/mol, respectively. Delocalization of lone pair electron is otherwise related to the resonance interaction in a molecular system. In this molecule, the main lone pair electron donation are from LP(1) N26 to the antibonding acceptor π*(C21-O27) (41.57 kcal/mol), from LP(2)O27 to the antibonding acceptor �*(C21-N26) (30.04 kcal/mol). Similarly, another lone pair electron donations are from LP(3) O29 to the antibonding acceptors �*(S28-O30) with stabilization energy 21.15 kcal/mol and from LP(3)O30 to the antibonding acceptor �*(S28-O29) with stabilization 21.63 kcal/mol. The interactions mainly include within the rings R1 and R3, and the nitrogen and sulphur atoms of the ring R2. The NBO analysis also describes the bonding in terms of the natural hybrid orbital LP(2) O27, which occupy a higher energy orbital (-0.27030 a.u.) with considerable p-character (99.92%) and low Bhawani D. Joshi, Manoj K. Chaudhary/ BIBECHANA 15 (2018) 131-139: RCOST p.134 occupation number (1.85623) and the other LP(1)O27 occupy a lower energy orbital (-0.70715 a.u.) with p-character (41.40%) and high occupation number (1.98474). Another natural hybrid orbital LP(2) O29, which occupy a higher energy orbital (-0.30236a.u.) with considerable p-character (99.91%) and low occupation number (1.80719) and the other LP(1)O29 occupy a lower energy orbital (-0.29619 a.u.) with p-character (24.15%) and high occupation number (1.98263). Similarly, the other NBO analysis describes in terms of the natural hybrid orbital LP(2)O2, which occupy a higher energy orbital (- 0.29619 a.u.) with p-character (99.92%) and low energy occupation (1.81031) and other LP(1)O30 occupy a lower energy orbital (-0.81342 a.u.) with p-character (23.45%) and high occupation number (1.98110).Thus, pure p-type lone pair orbital participates in the electron donation interactions in the compound. The results are tabulated in Table 2. Table 2.Selected Lewis orbitals (occupied bond or lone pair) with the valence hybrids corresponding to the various interactions in (3): A-donor, B-acceptor and(ED)-Electron density. Bond(A–B) EDA–B EDA (%) EDB (%) NBO Hybrid orbitals s (%) p (%) σ (C1–S28) 1.96350 54.34 45.66 0.7372(sp3.21)C+ 23.73 76.23 -0.69894 - - 0.6757(sp3.34)S 22.74 75.92 σ (C10–N26) 1.97989 38.37 61.63 0.6194(sp2.69)C+ 27.04 72.86 -0.80968 - - 0.7850(sp1.98)N 33.54 66.42 σ (C11–N26) 1.97750 37.98 62.02 0.6163(sp2.74)C+ 26.70 73.20 -0.79572 - - 0.7875(sp2.06)N 32.64 67.32 σ (C12–S28) 1.96303 53.74 46.26 0.7330(sp3.24)C+ 23.59 76.36 -0.69859 - - 0.6802(sp3.26)S 23.17 75.52 σ (C21–N26) 1.98018 35.37 64.63 0.5947(sp2.39)C+ 29.50 70.37 -0.81385 - - 0.8039(sp1.98)N 33.50 66.47 σ (C21–O27) 1.99417 35.16 64.84 0.5930(sp2.08)C+ 32.42 67.40 -1.09153 - - 0.8052(sp1.44)O 40.97 58.92 σ (S21–O29) 1.98590 35.28 64.72 0.5939(sp2.61)S+ 27.25 71.24 -0.98985 - - 0.8045(sp3.15)O 24.08 75.80 σ (S21–O30) 1.98233 35.24 64.76 0.5937(sp2.62)S+ 27.22 71.24 -0.97802 - - 0.8047(sp3.25)O 23.48 76.41 LP(1)N26 1.68652 - - (sp99.99) 0.30 99.69 -0.28427 - - - - - LP(1) O27 1.97547 (sp0.71) 58.58 41.40 -0.70715 - - - - - LP(2) O27 1.85623) - - P - 99.92 -0.27030 - - - - - LP(1) O29 1.98263 - - (sp0.32) 75.84 24.15 -0.81174 - - - - - LP(2) O29 1.80719 - - P - 99.91 -0.30236 - - - - - LP(3) O29 1.79804 - - (sp99.99) 0.12 99.79 -0.29967 - - - - - LP(1) O30 1.98110 - - (sp0.31) 76.54 23.45 -0.81342 - - - - - LP(2) O30 1.81031 - - P - 99.92 -0.29619 - - - - - LP(3) O30 1.77862 - - (sp99.99) 0.04 99.87 -0.29196 - - - - - The Mulliken charges provide partial atomic charges. They are explicitly sensitive to the choice of basis set used for theoretical calculation. They give qualitative results of the charge distribution to the related atoms. The NBO charges operate the electron density and are more reliable. Localized natural atomic orbitals can be used to describe electron density. The polarization bonds are considered in this method while no polarization is considered in the Mulliken system. The Mulliken and NBO charges obtained by B3LYP/6-311++G(d,p) basis have been listed in the Table 3. Their graphical comparison is shown in the Figure 2. Bhawani D. Joshi, Manoj K. Chaudhary/ BIBECHANA 15 (2018) 131-139: RCOST p.135 Table 3. Comparison of NBO and Mulliken charges by B3LYP/6-311++G(d,p) basis. Atom no. Mulliken charges (esu) NBO charges (esu) Atom no. Mulliken charges (esu) NBO charges (esu) 1 C -0.801065 -0.32909 16 H 0.072371 0.24827 2 C 0.338536 -0.18010 17 C 0.065647 -0.20784 3 H 0.138707 0.27189 18 H 0.077403 0.24719 4 C -0.174436 -0.23767 19 C -0.128778 -0.21207 5H 0.073405 0.25036 20 H 0.109145 0.26802 6 C 0.018242 -0.20909 21 C 0.159322 0.70133 7 H 0.090411 0.24828 22 C -0.308930 -0.74808 8 C 0.056851 -0.23514 23 H 0.163485 0.27063 9 H 0.065658 0.25055 24 H 0.141922 0.25093 10 C -0.394878 0.16009 25 H 0.146591 0.24921 11 C -0.003160 0.16753 26 N 0.352297 -0.49404 12 C -0.554110 -0.32425 27 O -0.278885 -0.57932 13 C 0.203503 -0.20626 28 S 0.861219 2.17709 14 H 0.133208 0.26962 29 O -0.340694 -0.92582 15 C -0.033144 -0.23002 30 O -0.249846 -0.91217 Fig. 2: Graphical representation of Mulliken and NBO charges. 3.2. Nonlinear optical (NLO) properties NLO phenomena have attractive attention because of their potential applications in optical communication, optical sensing, data storage, computing etc. [17, 18]. The first hyperpolarizability (β0) of the molecular system, and the related properties; mean polarizability (α0) and anisotropy of polarizability (∆α) have been calculated using B3LYP/6-311++G(d,p) basis set. First order hyperpolarizability is a third rank tensor that can be described by 3x3x3 matrix. The 27 components of 3d-matrix can be reduced to 10 components by Kleinman symmetry [19]. It can be given in the lower tetrahedral format. Energy of a system during weak and homogeneous electric field can be given as: E � E� ��μ�F�� � 12�α��F�F� � 16�β��"F�F�F"……��"�� Where E0 is the energy of unperturbed molecule, Fi is the field at the origin μi, αij and βijk are the components of dipole moment, polarizability and first hyperpolarizability, respectively. The components of hyperpolarizability tensor are listed in the Table 4. Bhawani D. Joshi, Manoj K. Chaudhary/ BIBECHANA 15 (2018) 131-139: RCOST p.136 Table 4.Dipolemoment (µ; Debye), polarizability (α x10-24 esu) and first hyperpolarizability (β0 x10-31 esu) by B3LYP/6-311++ G(d,p) method. Dipole moment Polarizability Hyperpolarizability μ$ -2.5505 α$$ -95.1487 β$$$ 6.4396 μ% 1.8587 α%% -125.1014 β%%% 9.9021 μ& -4.6646 α&& -124.3313 β&&& 4.3677 μ' 5.6319 4.2 (Urea) α$% -6.6784 β$%% -28.9734 α$& -2.1461 β$$% -19.6156 α%& 0.6211 β$$& -36.0926 α0 17.0223 β$&& -5.6695 ∆α 35.0921 β%&& 16.7140 β%%& -15.6364 β$%& -10.6509 β0 4.8308 1.947 (Urea) The total static dipole moment (μ�), mean polarizability (∆α�, anisotropy of polarizability (|α�|� and first hyperpolarizability (β�� can be expressed as [20]: μ� � (μ$� + μ%� + μ&�*+ �⁄ |α�| � 13 (α$$ + α%% + α&&* ∆α � 12 -(α$$ � α%%*� + (α%% � α&&*� + �α&& � α$$�� + 6α$$� .+ �⁄ β� � -(β$$$ + β$%% + β$&&*� + (β%%% + β$$% + β%&&*� + (β&&& + β$$& + β%%&*�.+ �⁄ The dipole moment, mean polarizability, anisotropy of polarizability and first hyperpolarizability of the title compound have been calculated and listed in the Table 4. These values are found to be higher than that of the standard NLO material urea [21]. In this study the first hyperpolarizability has been calculated nearly 2 times that of urea. Hence, the higher value of βo shows that the investigated compound has good nonlinear property. 3.3 Thermodynamic properties Computation of thermodynamic properties of molecules is important for both thermochemistry and chemical equilibrium. Statistical thermodynamics with the two key ideas, Boltzmann distribution and the partition function leads to the derivation of the equations utilized for computing thermochemical data in Gaussian programs. The total energy, zero-point energy, heat capacity (C0� ), entropy (S2,0� ), enthalpy (H0� ), dipole moment and the rotational constants of the molecular system were obtained directly from the output of Gaussian calculation employing B3LYP/6-311G(d.p) basis set and are listed in the Tables 5 (a & b). Table 5(a). Variation of different thermodynamic parameters with temperature. Temp (K) Enthalpy (kcal/mol) Specific heat (cal/mol-K) Entropy (cal/mol-K) 100 141.533 23.442 79.872 200 144.808 42.245 103.205 300 150.005 61.648 124.810 400 157.087 79.568 145.639 500 165.817 94.504 165.501 600 175.887 106.439 184.190 700 187.024 115.953 201.647 800 198.963 123.673 218.447 Bhawani D. Joshi, Manoj K. Chaudhary/ BIBECHANA 15 (2018) 131-139: RCOST p.137 The correlation between temperature and these thermodynamic properties are given in Figure3. The correlation equations are as follows: H0� � 138.660893 + 0.01732 T + 7.32786 x10<=T��R� � 0.99966� S0� � 55.97127 + 0.24566 T � 5.33423 x10<=T��R� � 0.9999� C2,0� � �1.05686 + 0.24515 T � 1.11082 x10