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Heme-type porphyrins can become distorted depending on their environment, altering their chemical and electronic properties. While trends have been established for several ruffle-distorted porphyrins, their research on synthetic models of heme-type porphyrins is limited. We identified a dynamic process on the ruffled porphyrin bis(2-methylpyridinato)iron(III)-Protoporphyrin-IX (2) that does not exist in bis(pyridinato)iron(III)-Protoporphyrin-IX (1). We modeled these molecules as {OMP(2-CH₃Py)₂Fe}${}^{+}$ and {[OMP](Py)₂Fe}${}^{+}$ respectively. Geometry optimization using density functional theory (DFT) suggests the ruffled conformation of 2 (angle x̄ of $-29.7^{\circ }$) and the planar conformation of 1. The calculated electron affinity and ionization potential vary depending upon ruffling. The calculated 0.253 eV difference in electron affinity and the 0.223 eV in ionization potential indicate that the reduction of the planar structure has a higher energy requirement than the ruffled-distorted structure but has a lower energy requirement for its oxidation. We found that these energy differences are not solely attributed to the distortion of the macrocycle. The difference is linked to the interaction between the d${}_{\text{x}\text{y}}$ orbital and the HOMO-1 3a${}_{2\text{u}}$, allowed by symmetry when a porphyrin ring has a ruffled conformation stabilizing the frontier orbitals, thus making the oxidation process have a higher energy barrier. On the other hand, the reduction process is facilitated by the interaction of metal d_π orbitals with the porphyrin 4e. These highlight the distinct differences between the ruffled and the planar conformations.

Structural, elastic, mechanical and electronic properties of pure and zinc-doped SrTiO₃ at the concentration in the range (1–10%) are studied by first-principles calculations. The structural parameters of synthesized compounds agree well with the standard data depicting the growth of stable compounds. A slight obvious increase in the lattice constant of 3.9245Å is observed in Zn-doped SrTiO₃ due to the deviation of the atomic radii of Zn and Ti. Elastic constants and mechanical parameters of SrTiO₃ are closer to their available theoretical and experimental data. The investigated compounds exhibit brittle behavior for all Zn ratios. The doping zinc concentration reduces the indirect band gap value. The doping concentration 2%, gives a band gap value closer to the experimental one. The band gap of pure SrTiO₃ is 1.827eV and after doping with Zn for concentration from 1% to 10%, the optimized values are 1.970, 1.886, 1.802, 1.718, 1.635, 1.552, 1.470, 1.389, 1.310, 1.231 and 1.154eV.

In this work, we used different approximations, namely the GGA and LDA of the density functional theory framework, to investigate the properties of the double perovskite Cs₂SnX₆ ($X=\mathrm{\text{Cl}}$, Br, I). We found that these materials are mechanically stable, and the calculated band gaps are 3.62eV for Cs₂SnCl₆, 2.33eV for Cs₂SnBr₆, and 1.00eV for Cs₂SnI₆, which agree well with the experimental results. The band structure reveals that the conduction band primarily arises from hybridization between the Sn-5s orbitals and the halogen p orbitals, while the valence band is predominantly composed of the halogen p orbitals. Additionally, we observed that all Cs₂SnX₆ compounds exhibit strong optical absorption in the ultraviolet region. Moreover, the absorption spectra edges shift toward the red from Cs₂SnCl₆ to Cs₂SnI₆. The thermoelectric properties have also been extensively characterized in this study. These favorable physical characteristics make Cs₂SnX₆ compounds attractive candidates for replacing expensive silicon cells in solar panels.

Visible and infrared spectroelectrochemistry of Fe(OEPone)(NO) (H₂OEPone = octaethylporphinone) were examined in methylene chloride and THF. The visible spectra of Fe(OEPone)(NO) were similar in both solvents. Unlike other ferrous porphyrin nitrosyls, a six-coordinate complex was formed with THF as a ligand. This led to two nitrosyl bands in the infrared spectrum. The absorbance of these bands depended on the concentration of THF in the solution. Solvation and coordination effects on the carbonyl and nitrosyl bands were observed for both the nitrosyl and reduced-nitrosyl complexes. DFT calculations were carried out to interpret the spectral changes.

Marquette University, Raynor Memorial Libraries, Chemistry Research Data: https://epublications.marquette.edu/chem_data/1/

Metal-free, magnesium, titanyl, and vanadyl tetrapyrazinoporphyrazines substituted with eight 2,6-diisopropylphenoxy groups at the peripheral positions were prepared and characterized by NMR, UV-Vis, magnetic circular dichroism (MCD), and mass spectrometry methods. In addition, the Pc^(2,6iPrPhO)8VO complex was characterized by EPR spectroscopy and X-ray crystallography. Reaction between TiCl₄ with 4,5-(2,6-diisopropylphenoxy)phthalonitrile in N,N-dimethylaminoethanol resulted in the formation of a red open-chain trimer, which was characterized by mass spectrometry and X-ray crystallography. Electronic structures of new compounds and their excited state properties were probed by Density Functional Theory (DFT) and Time-Dependent DFT (TDDFT) methods.

The synthesis and biological studies of meso-functionalized BODIPYs (BD-1 and BD-2) are reported. A pharmacophoric group (2-methyl-4-nitro-$N$-phenylaniline) was introduced at the meso-position of the BODIPYs. The substitution resulted in the red-shifted emission from BD-1 and BD-2as compared to the parent meso-aryl BODIPY. Molecular docking studies on PARP (Poly ADP-Ribose Polymerase) protein indicated efficient binding affinity of BD-2(-5.287) compared to BD-1. The cytotoxicity studies on triple-negative breast cancer cell line (MDA-MB-231) showed excellent photodynamic behavior of both compounds. Compound BD-2 showed excellent anti-proliferative activity in light with an IC${}_{50}$ value of 38 nm. However, in the dark condition both the compounds exhibited non-toxic behavior with 75–80% cell viability. The bioimaging studies indicated the cytoplasmic distribution of BD-1 and BD-2in the breast cancer cells.

The elusive PcFe(DABCO)₂ (Pc = phthalocyaninato(2-) ligand; DABCO = 1,4-diazabicyclo[2.2.2]octane) complex was prepared and characterized by UV-Vis, MCD, ¹H NMR, and Mössbauer spectroscopies. The X-ray crystal structure of this complex indicates the longest Fe-N(DABCO) bond distance among all known PcFeL₂ complexes with nitrogen donors as the axial ligands. The target compound is only stable in the presence of large access of the axial ligand and rapidly converts into the (PcFe)₂O $\mu$-oxo dimer even at a modest temperature. The electronic structure of the PcFe(DABCO)₂ complex was elucidated by DFT and TDDFT methods. The DFT calculations predicted a very small singlet-triplet gap in this compound. The femtosecond transient absorption spectroscopy is indicative of extremely fast ($\sim$200 fs) deactivation of the first excited state in PcFe(DABCO)₂ with a lack of formation of the long-lived low-energy triplet state.

Here we study the effect of metals on the characteristic Soret band of N-confused porphyrins. We used DFT calculations to study how this low-lying region of the spectrum of the NCP-2H isomer is affected by the introduction of transition metals with various ($d^2$, $d^3$, $d^4$ and $d^6)$ d-electron configurations. The spin ground state of these complexes is mostly dependent on the number of unpaired electrons, both with and without the presence of an axial ligand. The analysis of the electronic distribution and spin density showed that these unpaired electrons are often harbored by the N-confused porphyrin ring instead of on the metal. Time-dependent DFT results indicated that the aromatic system of porphyrin is disrupted in the N-confused isomer: instead of the typical large Soret band, this now gives rise to two peaks of much lower intensity. Most metallo-porphyrins exhibited similar optical properties, with the HOMO/LUMO orbitals showing a mixed metal/porphyrin character. The only exception was the Rh metalloporphyrin that exhibited a ligand-to-metal charge transfer band with increasing intensity as function of the ligand field. This suggests Rh is the only metal whose orbitals are higher in energy than the ligand’s, indicating that it is the only system where the redox processes occur on the metal.

The effect of perhalogenation (F, Cl) of porphyrazine macrocycle on the molecular structure, electronic and spectral properties of Al^III, Ga^III and In^III complexes bearing axial pentafluorophenoxy (C₆F₅O) group was investigated by DFT and TDDFT methods. Interactions between the axial pentafluorophenoxy group and porphyrazine core were carried out using the Symmetry-Adapted Perturbation Theory (SAPT0) method. According to the calculation results, the nature of the metal atom and peripheral halogenation slightly affect the geometry parameters. Analysis of the simulated spectra showed a bathochromic shift of the Q-band for perchlorinated complexes which correlates with narrowing of the HOMO-LUMO gap.

A comprehensive study of the structural, spectral and energetic properties of chloroboron(III) complexes of subphthalocyanine (H${}_{12}$SubPc, for the first time) and dodecafluorosubphthalocyanine (F${}_{12}$SubPc, reinvestigation) was performed by mass-spectroscopy (MS), gas-phase electron diffraction (GED), IR spectroscopy and quantum-chemical (QC) calculations. A synchronous GED/MS method showed that at T = 630 K and T = 540 K, thermally stable H${}_{12}$SubPc and F${}_{12}$SubPc molecular forms are present in the gas phase. The geometric structure of free molecules has been determined, in which the N₃-B-Cl fragment has the structure of a distorted tetrahedron, and the phthalocyanine skeleton has a dome shape. QC calculations of the geometry agree well with the GED results. The similarities and differences of the molecular structure in the gas and solid phases were discussed. It is shown, that despite the similarity of most geometric parameters, the H${}_{12}$SubPc and F${}_{12}$SubPc have significant differences in electronic characteristics, which determines the differences in their physicochemical properties. The interpretation of the experimental IR spectra was carried out. The distribution of potential energy of normal vibrations over the internal vibrational coordinates has been analyzed. The sublimation enthalpies of H${}_{12}$SubPc ($\mathrm{\Delta }$H${}_s$(589 K) = 135(5) kJ ⋅ mol${}^{-1})$ and F${}_{12}$SubPc ($\mathrm{\Delta }$H${}_s$(516 K) = 189(3) kJ ⋅ mol${}^{-1})$ were determined by the mass spectrometric Knudsen effusion method. The obtained data is important for designing processes employed in fabricating optoelectronic devices based on subphthalocyanines by PVD. Experimental geometric parameters for free molecules and vibrational frequencies can be used to calculate the thermodynamic functions of gaseous H${}_{12}$SubPc and F${}_{12}$SubPc.

In this work, the interaction of metal-free octaethylporphyrin (P) and a Mn(III) octaethylporphyrin chloride (MnP) films with various RNA nucleoside molecules (adenosine [A], cytidine [C], guanosine [G] and uridine [U]) was investigated to elucidate a possible molecular recognition. The porphyrin film-nucleoside interaction took place in solution, which was analyzed to quantify the nucleoside adsorption. The films were investigated by using microscopy and spectroscopic techniques (SEM, AFM, UV-Vis and IR), in addition to the in-plane film conductivity. Experimental results were correlated with DFT calculations to investigate binding energies, separation distances, and adsorption sites, among others. From these results, it was observed that purine bases were preferably adsorbed by the metal-free porphyrin film, while pyrimidine bases were adsorbed on the manganese porphyrin surface. Conductivity results exhibited the highest resistance for the bare metal-free film, but its conductivity increases after nucleoside adsorption, being the purine molecules the most resistive and the pyrimidine molecules the most conductive. In contrast, the Mn porphyrin film showed the highest conductivity, but after nucleoside adsorption, the resistivity increased for purine and pyrimidine bases, being pyrimidines the less conductive. DFT calculations showed binding energies PG>PA>PC>PU and MnPC>MnPG>MnPA>MnPU, which were consistent with experimental findings. In general, the main interactions took place between the porphyrin core and the pentose of the nucleoside, while MnP formed Mn porphyrin-nucleoside arrangements with octahedral geometry. The calculated UV-Vis spectra were in agreement with the experimental plots. From these results, changes in nucleoside adsorption can lead to a selective recognition of nucleoside molecules.

Herein, we report a novel layered lead bromide, (CH₃CH${}_2{)}_3$N${}^{+}$Br${}^{-}$(CH${}_2{)}_2$NH${}_3^{+})$PbBr₃, where bulky organic cations, (CH₃CH${}_2{)}_3$N${}^{+}$Br${}^{-}$(CH${}_2{)}_2$NH${}_3^{+})$, amino-ethyl triethyl ammonium [aetriea] were not only incorporated between the inorganic layers but also sandwiched within the inorganic [PbBr₆]${}^{4-}$ octahedral layered structure. The UV-Visible, photoluminescence spectroscopy (PL), X-ray diffraction (XRD) and a field-emission scanning electron microscope (FE-SEM) result show that the new perovskitoid has a microrod shape with an estimated bandgap of $\sim$3.05 eV. The structural and optoelectronic properties of the [aetriea]PbBr₃perovskitoid were further corroborated by first-principles density functional theory (DFT) calculations. Thermogravimetric analysis (TGA) data show good stability of the [aetriea]PbBr₃perovskitoid. Time-resolved photoluminescence (TRPL) decays from new [aetriea]PbBr₃perovskitoid showing 6 ns average lifetime. These results suggest that doubly charged cation hybrid perovskite materials are potential candidates for optoelectronic applications.

Flexible dielectric polymers that can withstand high electric field and simultaneously have high dielectric constant are desired for high-density energy storage. Here, we systematically investigated the impact of oxygen-containing ether and carbonyl groups in the backbone structure on dielectric properties of a series of cyclic olefin. In comparison to the influence of the –CF₃ pendant groups that had more impact on the dielectric constant rather than the band gap, the change of the backbone structure affected both the dielectric constant and band gaps. The one polymer with ether and carbonyl groups in the backbone has the largest band gap and highest discharge efficiency, while it has the lowest dielectric constant. The polymer without any ether groups in the backbone has the smallest band gap and lowest discharge efficiency, but it has the highest dielectric constant. Polymers that have no dipolar relaxation exhibit an inversely correlated dielectric constant and band gap. Enhancing the dipolar relaxation through rational molecular structure design can be a novel way to break through the exclusive constraint of dielectric constant and band gap for high-density energy storage.

In this study, we have calculated thermoelectric properties as a function of temperature and doping of the most stable phases of ZnO using first-principle calculations combined with semi-classical equation of Boltzmann. The nature of electrical conductivity is determined; the coefficient of Seebeck and figure of merit as a function of a charge carrier concentration of three structures studied are calculated. At high doping concentration, the rocksalt phase shows the best figure of merit.

Theoretical studies for the bioactive nature of the molecule, 4-aminopyridine 4-aminopyridinium thiocyanate, performed by density function theory (DFT) studies and molecular docking, were simulated by a molecular electrostatic potential surface. Frontier molecular orbitals, molecular properties, and density of state of the spectrum were computed. On account of $E_{\text{HOMO}}$ and $E_{\text{LUMO}}$ showing their notable polarizability and number of reactivity parameters, they were calculated by DFT. The function of new scoring is to calculate the free energy change on binding in docking studies that exploit flexible ligands with macromolecular protein targets that have been evolved and tested. The protein $\beta$-catenin (1JPW) was docked and compared to the standard drug molecule doxorubicin in molecular docking studies. The obtained 4-aminopyridine 4-aminopyridinium crystals revealed the results that confirmed the studied compounds have significant anti-cancer properties.

The capability and potential of C${}_{24}$, ScC${}_{23}$, TiC${}_{23}$, and NiC${}_{23}$ nanocages as novel candidates for delivery and sensor property of the Prothionamide (PA) drug in a biological system are investigated with density functional theory. The adsorption energy and thermodynamic parameters of PA@C${}_{24}$, PA@ScC${}_{23}$, PA@TiC${}_{23}$, and PA@NiC${}_{23}$ complexes in the absences and presence of static electrical field (SEF) (SEF${}_{z+0.01}$, SEF${}_{z+0.02}$, SEF${}_{z+0.03}$, and SEF${}_{z+0.04}$ a.u.) are calculated, and results indicated that the $E_{\mathrm{\text{ads}}}$, $\mathrm{\Delta }H$, and $\mathrm{\Delta }G$ values for all studied complexes in gas media are negative and exothermic. In the presence of water solvent, the $\mathrm{\Delta }\mathrm{\Delta }{G}_{(\mathrm{\text{sol}})}$ values of all drug and nanocage complexes are positive. The quantum descriptors, molecular electrostatic potential, the density of state, UV–visible spectrum, and dipole moment of all drug and nanocage complexes are determined and results are analyzed. The topological results of atom in molecule and the noncovalent interaction index display that the interaction of PA drug with C${}_{24}$ is electrostatic- and van der Waals-type. The computational results suggest that the ScC${}_{23}$, TiC${}_{23}$, and NiC${}_{23}$ nanocages can be used as good candidates for the delivery and sensor of the PA drug.

DFT calculations of ground-state hydrazine and benzohydrazide derivatives were performed by using hybrid functional B3LYP and CAMB3LYP with 6–31G (d, p) as basis set. The electric dipole moment ($\mu )$, polarizability ($\alpha )$ and molecular first hyperpolarizability ($\beta )$ were characterized in these compounds. The HOMO–LUMO energy gaps and the global chemical reactivity descriptors were computed by B3LYP and CAMB3LYP using 6–31G (d,p), while the excitation energies have determined by time dependent DFT (TDDFT). Besides, the stability and charge delocalization were studied by natural bond orbital analysis. Topological analyses such as atom in molecule (AIM), natural bonding orbital (NBO) and molecular electrostatic potential (MEP) have used to compute intermolecular interactions and in particular hydrogen bonds. The obtained first-order hyperpolarizabilities in the range of 1.5 × ${10}^{-30}$ to 30.2 × ${10}^{-30}$ esu revealed that the hydrazine and benzohydrazide derivatives have better NLO properties. The low-energy gap of 3.53 eV generates an intramolecular charge transfer, leading to the enhancement of the NLO activity in these compounds.

The study of interaction and adsorption of drug molecules on the active surface of noble metal nanocluster is of particular interest due to effective change in the properties of the drug molecules. Surface-enhanced Raman scattering (SERS) theoretical calculations were performed to investigate the adsorption properties of pretomanid (PTD) on pyramidal ${\text{Ag}}_{20}$/${\text{Au}}_{20}$/${\text{Cu}}_{20}$ metal clusters. The charge transfer process from the $M_{20}$ pyramids is revealed by MEP and electronic analysis. The frequencies of PTD are enhanced in the PTD–metal complexes due to the noticeable SERS effect, and the binding energies were calculated to be −36.2 kcal/mol, −46.3 kcal/mol and −43.6 kcal/mol with Ag, Au and Cu structures, respectively. For the PTD–metal clusters, there is an entire potential rearrangement due to adsorption process which is due to charge transfer and adsorptions as chemisorption. The polarizability variations are predicted in the order PTD–Au > PTD–Cu > PTD–Ag which contribute the SERS enhancement due to adsorption. Changes in thermodynamic parameters reveal that adsorption is exothermic and at the same time spontaneous with ordered interactions due to the negative values. There is a redshift for the ultraviolet–visible (UV–vis) absorption of PTD–metal complexes with a lowering intensity in comparison with that of PTD, more likely indicating a chemisorption process. SERS enhancement factors are remarkable due to adsorption of conformationally flexible PTD on metal clusters. The noncovalent interactions between PTD and the metal pyramids were also determined. The study provided key information on designing a molecular structure with a good pharmacological profile by calculating bioactivity and drug similarity parameters for bioactive drug molecules.

Using first principles, the electrical response of carbon nanocones (NC) to the drug benzamide (BZE) was investigated using density functional theory (DFT). The adsorption energies of BZE at the nanocone’s bottom (Complex I), side (Complex II), and top (Complex III) are −88.35 kcal/mol, −45.46 kcal/mol and −48.73 kcal/mol. The two other adsorptions, Complexes II and III are physisorption, however, the high value of Eads in the case of Complex I with the drop in bond lengths suggests that Complex I adsorption is chemisorption. The electrical conductivity has risen as a result of the considerable decrease in the nanocone energy gap (from 0.63 eV to 0.61 eV, 0.61 eV and 0.60 eV) caused by the adsorption of BZE. It suggests that the nanocones would be a good fit for the electronic sensors and an appropriate choice for BZE detection. Additionally, the BZE adsorption influences the nanocone’s workfunction, which is reduced by approximately 45.19%, 2.8% and 2.05% for complexes I to III. This suggests that the nanocone could be a workfunction-based sensor for the detection of BZE. The increase in binding affinity in complexes reveals that the nanocones will act as a drug delivery carrier. Theoretically, anticipated Raman spectra of BZE and complexes show SERS activity and inactive normal Raman modes are active in the Raman spectrum of complexes. Compounds II and III exhibit weak noncovalent interactions (NCI) and due to the presence of covalent bonding interaction in compound I, significant changes in other bonding and nonbonding electron densities are observed compared to compounds II and III.

This study explores the interactions between hexanal Schiff bases and a B12N12 nanocage, employing density functional theory (DFT) calculations to deepen our understanding of noncovalent bonds. Hexanal, a key component in tea, plays a vital role in prolonging the shelf-life of various plant-based products by inhibiting phospholipase-D. Our research initially focused on synthesizing Schiff bases through the condensation of hexanal with nucleobases and an amino acid. We then conducted a series of DFT calculations, including geometry optimizations, frontier molecular orbital (FMO), natural bond orbital (NBO) and noncovalent interactions (NCI) assays, using Gaussian 16 and ORCA 5.0.2 software packages. This study reveals that hexanal Schiff bases form stable complexes with the B12N12 nanocage, exhibiting notable dative coordinate bonding. The FMO analysis indicates a significant energy gap variation among the complexes, with CSB2 showing the lowest energy gap, hinting at its high reactivity. In the LED assay, CSB2 demonstrates the lowest decomposition energy, highlighting its potential stability. The AIMD simulations provide insights into the electronic motions of these complexes, underscoring their dynamic nature. Our NBO analysis offers a comprehensive view of the electron distribution within these complexes, emphasizing the significance of nitrogen and boron atoms in the bonding process. The NCI assay sheds light on the predominant van der Waals and steric interactions contributing to the stability of the complexes. This investigation provides a detailed account of the NCI between hexanal Schiff bases and the B12N12 nanocage. The findings not only contribute to the field of noncovalent bonding in inorganic-fullerene structures but also open avenues for future applications in material science and molecular engineering.