Biomedicine and Chemical Sciences 1(3) (2022) 138-146 New Homo and Heterobinuclear Macrocyclic Complexes Bearing Isatine: Structural Characterization, Thermal Study and DFT Calculations Anaam Rasheeda, Senan Albayatib, Sarab Alazawic, Enas Zuhaird, Mudeer Merzae, Khalil Abidf* a,b,c,d,e,f Department of Chemistry, College of Science, Mustanseriyah University, Baghdad - Iraq A R T I C L E I N F O A B S T R A C T Article history: A new metal-free macrocyclic Schiff base ligand bearing two metal cavities incorporated with two sets of N3O2 donor atoms derived from 2, 6-diaminopyridine and isatine was synthesized. The new ligand was used to prepare homo and hetero binuclear macrocyclic Schiff base complexes with Ni (II), Cu (II), ZrO (II) and Ba (II) metal ions. The ligand and metal complexes were characterized using Fourier transform infrared (FT-IR), UV–vis, mass spectroscopy, elemental analysis (CHN), thermo gravimetric analysis (TGA), magnetic susceptibility, and molar conductivity measurements. The DFT calculations using the B3LYP functional method have been applied to obtain the geometry and electronic properties of the ligand and its metal complexes to support the experimental data. To describe the reactivity of the title molecules, the HOMO and LUMO levels and Mulliken atomic charges were determined. Copyright © 2022 Biomedicine and Chemical Sciences. Published by International Research and Publishing Academy – Pakistan, Co-published by Al-Furat Al-Awsat Technical University – Iraq. This is an open access article licensed under CC BY: (https://creativecommons.org/licenses/by/4.0) Received on: February 28, 2022 Revised on: March 28, 2022 Accepted on: March 28, 2022 Published on: July 01, 2022 Keywords: Bimetal Complexes Diaminopyridine Schiff Base Supermolecule Ligands 1. Introduction 1Coordination chemistry of macrocyclic ligands have demonstrated an extensive intrigue over the most recent two decades (Archibald, 2009; Chu, et al., 2008). The utilization of macrocyclic ligands as models for protein-metal binding sites in biological systems, such as the synthetic ionophores, models for the magnetic exchange phenomena, therapeutic reagents in chelate therapy for treatment of metal intoxication and the cyclic antimicrobials that hold their anti-toxin activities to specific metal complexation raises the importance of new macrocyclic ligand designing (Kilpin, et al., 2007; Tušek-Božić, et al., 2007). Macrocyclic systems got extra significance over the acyclic ligand systems as the macro systems are thermodynamically stabilized and kinetically delayed toward metal dissociation and substitution by the so-called ‘macrocyclic effect’. The *Corresponding author: Khalil Abid, Department of Chemistry, College of Science, Mustanseriyah University, Baghdad - Iraq E-mail: abidk56@yahoo.com How to cite: Rasheed, A., Albayati, S., Alazawi, S., Zuhair, E., Merza, M., & Abid, K. (2022). New Homo and Heterobinuclear Macrocyclic Complexes Bearing Isatine: Structural Characterization, Thermal Study and DFT Calculations. Biomedicine and Chemical Sciences, 1(3), 138-146. DOI: https://doi.org/10.48112/bcs.v1i3.187 incredible significance of macrocyclic systems in chemistry properly because of their particular chelation towards certain metal particles relying upon the number, size of the cavity, type, number and position of their donor atoms. The ionic radii of the metal centers and the coordination property of the counter ions (Ceramella, et al., 2022) gives them the exceptional significance in the field of bioinorganic chemistry (Gull, et al., 2017; Ikotun, et al., 2019) and the potential therapeutic, analytical and industrial applications (Chandra & Kumar, 2004; Chandra, et al., 2006). Schiff base metal complexes show a broad range of biological activity that is usually increased by complexation with the metal ion. It have striking properties such as antibacterial, antifungal, antiviral, antiinflammatory, anti-tumor and cytotoxic activities, plant development controller, enzymatic activity and applications in pharmaceutical fields (Bitu, et al., 2019). Buildup of diamines and dialdehydes to form Schiff base macrocycles has been utilized by numerous researches to frame both small and enormous stable macrocycles, usually templated with transition metals (Ma, et al., 2006; Beckmann & Brooker, 2003). Nontemplate macrocyclic Schiff base synthesis process requires the use of rigid starting carbonyl groups and high dilution conditions. This process is very efficient and the metal free product can be obtained in good yield. Synthetic macrocyclic complexes mimic some naturally occurring macrocycles because of Contents lists available at: https://journals.irapa.org/index.php/BCS/issue/view/12 Biomedicine and Chemical Sciences J o u r n a l h o m e p a g e : https://journals.irapa.org/index.php/BCS 20-BCS-830-187 https://journals.irapa.org/index.php/BCS/index https://irapa.org/ https://irapa.org/ https://en.atu.edu.iq/ https://creativecommons.org/licenses/by/4.0 mailto:abidk56@yahoo.com https://doi.org/10.48112/bcs.v1i3.187 https://journals.irapa.org/index.php/BCS/issue/view/12 https://journals.irapa.org/index.php/BCS Rasheed, Albayati, Alazawi, Zuhair, Merza & Abid Biomedicine and Chemical Sciences 1(3) (2022) 138-146 139 their resemblance with many natural macrocycles, such as metalloproteins and metalloenzymes. Some macrocyclic complexes have gotten exceptional consideration as a result of their have received special attention because of their mixed soft–hard donor character and versatile coordination behaviour and because of their pharmacological properties, i.e., lethality against bacterial and contagious development. One significant point of intrigue is to create homo and hetero-multimetallic complexes since they show distinct reactivity design when compared with comparing monometallic complexes. The magnetic interactions and coupling between the metal ions present in such complexes play key role in both natural and synthetic catalysts. Several attempts to prepare heterobinuclear complexes from the mononuclear ones were unsuccesfsull, yielding the starting materials or homobinuclear complexes (Mohapatra, et al., 2012; Borisova, et al., 2004). Isatin considered as one of the raw materials for the drug synthesis due to its cis α-dicarbonyl moiety, it is one of the essential substrates to synthesize metal complexes. Deprotonated or alone, it might be located in the mammalian tissues, stemming from the interests in pharmacological and biological characteristics of isatin derivatives (Alkam, et al., 2021). The present work is focused on synthesis and structural characterization of new macrocyclic Schiff base ligand bearing isatine moiety and its homo – and heterobinuclear complexes with Ni (II), Cu (II), ZrO (II) and Ba (II) metal particles. Additionally, the results of the calculations of DFT as well as geometry optimization of the synthesized molecules were reported. 2. Materials and Methods All chemicals were analytical grade and used without any modification. Electronic spectra were obtained by use of a Varian UV–Vis spectrophotometer, molar conductivity measurements by use of a WTWF56 apparatus with absolute ethanol as solvent, and FTIR spectra by use of a Shimadzu spectrophotometer, mass spectra were recorded by use of Schimadzu mass spectroscopy, Magnetic susceptibility measurements were carried out using of Curie balance in the Chemistry Department, College of Science, Mustansiriya University. Flame atomic absorption, Elemental analysis (C.H.N.) performed with an elemental analyzer (EA) and thermal stability (weight changes) of the samples were recorded by Mettler Toledo in the temperature up to 600 °C in the Ibn Alhatham College of Pure Science, University of Baghdad, Iraq. The DFT calculations using B3LYP functional method has been applied to obtain the geometry and electronic properties of the ligand and its metal complexes. 2.1. Preparation of Preliminarily Compound This compound was prepared according to the procedure mentioned in literature (Dileepan, et al., 2018). 2 g, 0.013 mol of isatin dissolved in 30 mL of ethanol and 0.54 g, 0.013 mol of NaOH dissolved in 20 mL of distilled water and 0.52 g, 0.006 mol of dibromoethane were mixed in a 250 mL round bottom flask, and this mixture was heated at 70 °C in water bath for 16 hr. After completion of the reaction as monitored by TLC, the reaction mixture was cooled and washed with hot water. The solid residue was extracted twice with dichloromethane (50 and 20 mL respectively) and the solution was brought to dryness, and then washed with methanol. The obtained solid was dried under vacuum to give a pale yellow colored product. 2.2. Synthesis of Metal Free Macrocyclic Schiff Base Ligand 0.002 mol of compound 1 dissolved in ethanol (20 mL) mixed with 0.002 mol of 2,6-diaminopyridine dissolved in absolute ethanol (30 mL) and few drops of glacial acetic acid were added as catalyst. The mixture was refluxed for 8 hr, cooled and filtered. The solid product was recrystallized from ethanol to afford a bright orange crystals in 84 % yield (Scheme 1). N H O O 2 + Br Br base, catalyst EtOH, reflux N N O O O O Istain N N O O O O 2 + 2 N NH2NH2 EtOH, HOAC reflux Cl 4 dibromo ethane +2 +2 +2 M= Ni , Cu , Ba N N N N O NN O N OO N N N M M N N N N O NN O N OO N N N Scheme 1 Synthesis of Macrocyclic Schiff base ligand(L) 2.3. Synthesis of Homobinuclear Metal Complexes To a stirred solution of 0.001 mol of the ligand in ethanol (40 mL) and 0.002 mol of metal salt ( NiCl2.6H2O, CuCl2.2H2O, ZrOCl2.6H2O and BaCl2.2H2O) in ethanol (30 mL) were mixed under reflux for 3 hr. The resultant precipitate were cooled, filtered off and washed with cold water and ethanol then dried in oven for 3 hr at 70 oC. 2.4. Synthesis of Heterobinuclear Metal Complexes The mononuclear metal complexes were obtained first by the reaction of 0.001 mol of NiCl2.6H2O in ethanol (20 mL) and slightly access (0.001 mol) of the macrocyclic ligand in ethanol (20 mL) at reflux for 3 hr to afford a brown precipitate which filtered off and dried. 0.001 mol of this complex in warm ethanol (20 mL) was mixed with 0.001 mol of CuCl2.2H2O in warm ethanol (20 ml). A green precipitate of heterobinuclear complex ( NiCuL.Cl4) was formed instantaneously, stirring to complete the reaction for additional 1 hr, filtered off, washed with cold ethanol and dried in oven for 3 hr at 70 OC, Table 1. 2.5. Computational Details Gaussian 09 (with Gaus view 5.08) suite of programs has been conveyed for completing all calculations and assessments of the study. Complete optimization of all complex’s geometries at B3LYP at the level LanL2DZ was performed. Accordingly, it is sent regularly alongside the techniques for density functional for completing the investigation of transition metals containing frameworks. Rasheed, Albayati, Alazawi, Zuhair, Merza & Abid Biomedicine and Chemical Sciences 1(3) (2022) 138-146 140 Table 1 Some physical and chemical properties of the ligand and metal complexes %Elemental Analysis Found(Calc.) Conduct. M.P. M.Wt Colour Compound ohm- 1 cm2 / mol 0C g / mol M% N H C ---- 17.81 3.81 70.22 ---- 166- 168 786 Deep L (17.78) (3.79) (70.2) Orange C46H30N10O4 6.82 15.39 3.31 60.4 87 220 915.7 Light Brown [NiL]Cl2 (6.41) (15.28) (3.27) (60.28) 11.42 13.39 2.86 52.8 156 252d* 1045 Green [Ni2L(H2O)2]Cl4 (11.19) (13.37) (2.85) (52.77) 12.33 13.27 2.84 52.32 153 260 1055 Deep Brown [Cu2L]Cl4 (12.02) (13.19) (2.83) -51.99 23.29 11.64 2.49 45.92 158 300d* 1202 Light Green [Ba2L] Cl4 (23.01) (11.59) (2.42) (45.88) 15.43 12.25 2.62 48.33 155 274d* 1142 Brown [(ZrO)2 L ]Cl4 (14.99) (12.20) (2.57) (48.28) 12.15 13.41 2.91 52.67 151 240d* 1050 Olive Green [NiCu( L)]Cl4 -11.63 (13.33) (2.85) (52.57) 3. Results and Discussion 3.1. FT – IR spectra The (FT-IR) spectra were recorded in the region 4000–400 cm−1 by using KBr disc. The IR spectra of preliminarily compound showed a characteristic bands at 3065, 3271 and 1731 cm-1 attributed to aromatic, aliphatic (C– H) and ( C = O) groups respectively (Silverstein & Bassler, 1962; Racles, et al., 2013). The formation of macrocyclic Schiff base ligand was confirmed by the presence of the azomethine band at 1656 cm-1 while the position of the carbonyl group was shifted to 1722 cm-1. The spectra of metal complexes showed clear red shift in the absorptions of these bonds (Venkatesh & Geetha, 2015), these indicates the coordination of the Ni (II), Cu (II), ZrO (II) and Ba (II) metal ions with these active sites. The mononuclear complexes showed two absorption bands for each of (C=O) and ( C=N ) bonds which probably assigned to one corrdinated and one uncoordinated cavity. The presence of coordinated water molecule for Ni (II) complex was indicated by the appearance of a broad band around 3450 cm-1 and two weak bands at 765, 712 cm-1 respectively due to (-OH) rocking and wagging mode of vibrations. The frequency of Zr = O band was located at 1418 cm-1, while two new bands appeared in the complexes around 550 and 450 cm-1; these were attributed to the coordinated M–N and M–O bonds respectively (Nakamoto, 2009), see Table S1 in supplementary data. 3.2. UV–Visible Spectra The ligand and metal complexes were recorded in 200 – 800 nm using concentration of 0.001 M and absolute ethanol as a solvent. The high energy around 217 nm is probably related to π→π* transitions centered on the benzene moiety. Other absorption bands were observed around 260 and 322 nm probably assignment to n→π* transitions. The electronic spectra of metal complexes showed considerable red shift (15 – 30 nm) in the λmax values of n→π* absorption bands in comparison with the free ligands. These red shifts are presumably due to the nephelauxetic effect and are regarded as a measure of covalence of the bonding between the metal ion and the ligands, suggest weak covalent nature of the metal–ligand bonds (Nockemann, et al., 2006). The new low energy band appeared around 440 nm for the metal complexes probably pronounced as charge transfer transition character. Three bands were recorded for the Ni (II) complex at 632, 491 and the third band combined with the charge transfer bands around 410 – 450 nm, these band attributed to the transitions 3A2g → 3T2g (F), 3A2g→3T1g (F), and 3A2g→3T1g (P), respectively, suggesting octahedral geometry. The relatively weak intensity broad band at 478 nm for Cu (II) complex assigned to 2B 1g →2A 1g transition with high magentic moment observed, bond angels and length obtained for coordinated Cu – O and Cu – N bonds., confirming the square planar geometry around Cu+2 metal ion (Gliemann, 1985). For ZrO (II) and Ba (II) complexes and their configuration according to DFT calculation were square pyramid and tetrahedral geometry respectively (Figure 4). 3.3. Mass Spectra Mass spectra were recorded using a Direct Injection Probe.The mass spectra of the ligand(L) illustrated in Figure 1 showed a molecular ion peak at m / e = 786 g / mole which agree well with the empirical formula of the ligand, C46H30N10O4. The base peak with relative I = 100 % of the peak at m / e= 57 may be resulted from the extreme stability of the fragment [m / e = C2H3NO . Rasheed, Albayati, Alazawi, Zuhair, Merza & Abid Biomedicine and Chemical Sciences 1(3) (2022) 138-146 141 Fig. 1. Mass spectra of the ligand (L) 3.4. Magnetic Measurements The magnetic susceptibility for the complexes was recorded in the solid state at 298 K using Faraday’s method. All the prepared complexes of the Ni (II), ZrO (II) and Ba (II) ions showed diamagnetic properties since no electrons found in the valence shell of orbital for later two ions while it confirmed a low spin for Ni (II) complex. The homobinuclear Cu (II) and heterobinuclear Ni (II) Cu (II) complexes recorded a relatively high magnetic moment of 2.52 B.M. which support the squar planner – squar planar geometry for the first and octahedral – squar planar geometries for the second. 3.5. Molar Conductivity Measurements The molar conductivity measurements for the complexes were carried out using a concentration of 10 – 3 M and absolute ethanol as a solvent and CON 510 bench conductivity meter (cell constant, K = 1.0) in order to assist us in the elucidation the formula and structures of the prepared homo- and heterobinuclear complexes. The data observed for molar conductance of bimetal complexes showed molar conductivity values in the range (124.3-146.5 Ω-1 cm2 / mol) which suggest a 1:4 electrolyte type, while the Ni (II) mononuclear complex showed conductivity of 64 Ω-1 cm 2 / mol agree with 1:2 electrolyte type. The collected results supports the four coordination number with equilibrium environments of squar planner geometry around Ni (II) and Cu (II), tetrahedral around Ba (II) and squar pyramide geometry around ZrO (II) ions. 3.6. Thermogravimetric Analysis of Metal Complexes Thermogravimetric analyses of complexes were performed under air atmosphere at the heating rate 10oC / min up to 600 oC. The thermogram of Ni (II) complex recorded three stages of weight loose. The first one showed the initial weight loss in the temperature around 250 oC probably due to the loss of coordinated water molecule (Bottei & Quane, 1964). The anhydrous complexes remain stable up to 425 oC then the complex suffered a rapid and big weight loose due to the decomposition of macrocyclic ligand of the complex molecule followed by the final residue of NiO above 590 oC. The TGA curve of the other complexes do not show any weight loss below 290 °C and shows only two stages of mass loss at the temperature around 295 oC and 591 oC corresponding to the decomposition of the complex for the first and the formation of a thermally stable metal oxide for the second (Cifelli, et al., 2013). It is strong evidence, which represent that these complexes were devoid of lattice water as well as coordinated water in the coordination sphere (See Figures 2 and 3). 3.7. Structural Analysis The optimized geometrical structures of the L and Ni (II), Cu (II) , ZrO (II) and Ba (II) complex molecules were shown in Figure 4. The selected bond lengths, bond angles, dipole moments and ev of HOMO, LUMO of these structures were calculated, Table S2 and S3 in supplementary data. The optimized structure obtained were agree with the suggested configurations of the metal complexes based on the experimental data. It gives a good evidence of octahedral geometry for Ni (II) stabilized by one water molecule with N3O2 atoms around metal atom, while the structures of Cu (II) , Ba (II) and ZrO (II) complexes were squar planner, tetrahedral and square pyramid respectively stabilized by N2O2 atoms. Rasheed, Albayati, Alazawi, Zuhair, Merza & Abid Biomedicine and Chemical Sciences 1(3) (2022) 138-146 142 Fig. 2. TGA for [Cu2 L] complex Fig. 3. TGA for [Ba2 L] complex Fig. 4. The optimized structures of L, ZrO (II), Ba (II), Ni (II) and Cu (II) complexes respectively Rasheed, Albayati, Alazawi, Zuhair, Merza & Abid Biomedicine and Chemical Sciences 1(3) (2022) 138-146 143 3.8. HOMO-LUMO and MEP Analysis In a molecule, the highest energy level (EHOMO) that is full of electrons and the lowest energy level (ELUMO) that is lack of electrons play an important role in electrical, optical, and molecular charge transfer (Arshad, et al., 2017; Sherzaman, et al., 2017). While HOMO orbitals tend to give electrons, which in turns it is suitable to form a coordination bonds with the metal ions, LUMO orbitals suffers luck of electrons and tends to receive them. These molecular orbitals (MOs) are important because their interaction with other molecules is through HOMO-LUMO priority orbitals. It shows the HOMO orbitals of the ligand were localized on the carbonyl group of the the isatin ring and azomethine group, while LUMO orbitals were localized on the benzene ring. Molecular electrical potential surface (MEP) also known as electrostatic potentials map, or electrostatic potential energy map, was determined for the ligand. It illustrate the charge distributions of molecule three dimensionally. This map allows us to visualize variably charged regions of a molecule. Knowledge of the charge distributions can be used to determine how molecules interact with one another. They also allow us to visualize the size and shape of molecules. In organic chemistry, electrostatic potential maps are invaluable in predicting the behavior of complex molecules (see Figures S3, S4 and S5 in supplementary data). 4. Conclusion This work is aimed at synthesizing new homo and heterobinuclear macrocyclic complexes through the two steps of substitution reaction to afford a macrocyclic Schiff base ligand bearing two cavities consisting of N2O2 donor atoms ready for complexing. The investigation of the collected experimental data of the ligand and the metal complexes combined with the DFT calculations showed the geometry of octahedral for Ni (II), squar planner for Cu (II), tetrahedral for Ba (II) and squar pyramide for ZrO (II) with a 2:1 molar ratio (M:L). Acknowledgments The authors would like to thank the Ibn Alhaitham College of Pure Science, University of Baghdad for spectral data and University of Mustansiriyah, College of Science for providing the financial support. Competing Interests The authors have declared that no competing interests exist. References Alkam, H. H., Atiyah, E. M., Majeed, N. M., & Alwan, W. M. (2021). 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SOJ Materials Science & Engineering, 3(2), 1-5. http://dx.doi.org/10.15226/sojmse.2015.00121 Supplementary Data for Manuscript Table S1 Major Infra – red spectra of the ligand and complexes (cm-1) Compound ν(C=O) ν(C=N) ν(M-N) Ν(M-O) C46H30N10O4 1722 1656 - - [NiL]Cl2 1707, 1719 1641, 1653 565 472 [Ni2L(H2O)2]Cl4 1705 1643 563 468 [Cu2L]Cl4 1695 1638 570 480 [Ba2L] Cl4 1702 1635 543 443 [(ZrO)2 L ]Cl4 1710 1650 525 111418(Zr=O), 430 https://doi.org/10.1016/j.jphotobiol.2018.04.029 https://doi.org/10.1002/bbpc.19850890122 https://doi.org/10.1016/j.micpath.2017.07.030 https://dx.doi.org/10.4314/jasem.v23i11.8 https://doi.org/10.1016/j.poly.2006.08.009 https://doi.org/10.1007/s11243-005-6336-9 https://doi.org/10.5012/jkcs.2012.56.1.062 https://doi.org/10.1002/0470027320.s4104 https://doi.org/10.1021/ja0640391 https://doi.org/10.1080/15685551.2012.747161 https://doi.org/10.1016/j.molstruc.2017.07.054 https://doi.org/10.1021/ed039p546 https://doi.org/10.1016/j.poly.2006.12.012 http://dx.doi.org/10.15226/sojmse.2015.00121 Rasheed, Albayati, Alazawi, Zuhair, Merza & Abid Biomedicine and Chemical Sciences 1(3) (2022) 138-146 145 Fig. S1. Infrared spectra of the macrocyclic ligand Fig. S2. UV - vis spectra of the macrocyclic ligand Table S2 Selected calculated bond lengths [A] for ligand and metal complexes Bond length Ligand Zr+2 Complex Ni+2 Complex Ba+2 Complex Cu+2 Complex N4-C1 1.2474648 1.3243446 1.3917231 1.3398398 1.321782 C5-N3 1.5021387 1.4701977 1.4669541 1.4975964 1.34046 N11-C9 1.3330117 1.3325369 1.4680986 1.4188147 1.070128 O12-C9 1.2508565 1.3240249 1.3278668 1.3392561 1.069501 N13-C10 1.1999732 1.3549573 1.3986174 1.3335973 1.21922 C14-N13 2.4851072 2.6151162 2.7521585 2.550753 1.60364 N22-C15 1.3425598 1.3648472 1.1523757 1.3990587 1.36976 C24-N23 2.4293309 2.3138288 2.2440847 2.3484169 2.375025 C28-N27 1.4308501 1.4306165 1.5105538 1.4286202 1.358347 N45-C44 1.4369328 1.3743734 1.4635699 1.3976842 1.370042 O46-C44 1.2391514 1.2967463 1.3490889 1.2652729 1.269845 N48-C47 1.2856163 1.3174084 1.3831214 1.3294661 1.265656 C49-N4 1.3505834 1.3713561 1.4370666 1.3705226 1.395935 C50-N48 1.3552004 1.3747616 1.438784 1.3773546 1.305634 N54-C50 1.3661941 1.3809157 1.2268407 1.375835 1.311126 Zr+2 complex Ni+2 complex Ba+2 complex Cu+2 complex Zr89-O87 1.792592 Ni88-N13 1.78384 Ba88-N23 2.30067 O91-C14 1.385641 Zr89-N54 2.205855 Ni88-O90 1.64846 Ba88-O26 2.3614 Cu92- N48 2.511504 O90-Zr89 1.78707 Ni89-N54 1.82018 Ba89-N48 2.32862 Cu93-N90 2.417429 Table S3 Selected calculated bond angles [°] for ligand and metal complexes Angle Ligand Zr+2 complex Ni+2 complex Ba+2 complex Cu+2 complex N11-C9-C7 36.038634 125.01221 111.01978 35.092056 115.1945 O12-C9-C7 119.95526 94.631367 120.42627 88.715914 116.8096 N13-C10-C9 134.90826 112.76526 105.05712 124.72992 124.6363 C14-N13-C10 152.15495 119.60255 128.73203 141.60652 105.4174 C15-N13-C14 27.845023 140.08967 13.83729 165.78147 109.0268 C17-C15-N13 141.38676 125.47268 98.58692 130.42284 135.0306 H19-C14-N13 94.210793 102.73663 110.27224 97.940828 111.3392 N22-C15-N13 111.56988 104.03602 23.034609 28.942513 109.3465 N23-C16-C15 143.70809 123.67043 108.95162 128.4596 111.30973 C24-N23-C16 166.75269 155.5603 177.49594 150.91703 150.98939 C25-N23-C16 158.98864 142.09255 140.93235 145.79547 149.8149 O26-C24-N23 98.355023 91.64386 78.281407 92.970103 94.6774 N27-C24-N23 132.78311 141.78932 146.41317 140.30583 146.6738 N45-C44-C39 33.803667 28.589213 109.10807 34.37228 92.5908 O46-C44-C39 93.448943 99.237801 110.68447 92.653026 112.2974 C49-N4-C1 179.77163 144.23024 140.6656 142.75181 143.7659 C51-C50-N48 128.23582 134.36774 161.83033 130.35349 131.6464 C52-C49-N4 126.70335 134.629 161.41359 130.50019 151.6861 N54-C50-N48 113.29895 102.74245 85.446002 110.36582 104.5776 C66-C1-N4 124.44843 131.44729 132.21709 128.86044 129.599 Zr+2 complex Ni+2 complex Ba+2 complex Cu+2 complex O- Zr = O 89.69 N- Ni- O 83.36 N- Ba- N 102.99 N- Cu- O 88.95 O- Zr - O 102.13 O- Ni- N 110.53 O- Ba- N 61.46 O- Cu- O 91.36 O- Zr – N 91.84 N- Ni- N 59.77 N- Ba- O 49.98 O - Cu-N 88.06 Rasheed, Albayati, Alazawi, Zuhair, Merza & Abid Biomedicine and Chemical Sciences 1(3) (2022) 138-146 146 Table S4 Calculated molecular orbital energy values of the ligand and metal complexes Property Ligand Zr complex Ni complex Ba complex Cu complex E total (Hartree) -2583.5414 -2860.2273 -3107.2850 -2667.4827 -3085.8781 Dipole moment (Debye) 14.2375 16.4800 6.7305 9.3231 8.1660 E HOMO (eV) -5.2775 -5.0466 -5.2584 -4.8203 -4.5188 E LUMO (eV) -3.1760 -3.4486 -3.2005 -2.8979 -3.3485 E LUMO - E HOMO (eV) 2.10148 1.5976 2.0579 1.9224 1.1703 IP (eV) 5.2775 5.0466 5.2584 4.8203 4.5188 EA (eV) 3.1760 3.4486 3.2005 2.8979 3.3485 ᵡ (eV) 4.2265 4.2474 4.2294 3.8591 3.9336 μ (eV) -4.2265 -4.2474 -4.2294 -3.8591 -3.9336 η (eV) 1.0507 0.7988 1.0289 0.9612 0.5851 S (eV) 0.95170 1.2518 0.9719 1.0403 1.7091 Fig. S3. The optimized structures of ligand with atoms numbers Fig. S4. MEP of the Ligand Fig. S5. The HOMO and LUMO frontier molecular orbitals of the ligand.