Photoluminescence in a Glucose-coated Sila-fullerane and Its Nanomedicine Applications

Abstract In this study, we introduce nano-baits that are formed based on the binding of glucose in a silicon nanoparticle. Sila-dodecahedrane has been selected among of four other famous nanostructures, due to its high stability, biocompatibility and its ability to engineer electronic features. Because of the glucose attached to nano-baits, they are attractive to cancer cells that consume high glucose. In this research, two nano-baits have been modeled with the chemical formulas of Si20H19C6H11O6 and Si20H13(C6H11O6)7. Their optimal structures are obtained using density functional theory (DFT). For this, we use the B3LYP hybrid functional and 6-31+g(d,p) basis set. Vibration frequency calculations show that the glucose binding of a sila-dodecahedrane has a stable bond. These nano-baits with photoluminescence determine the location of cancer cells. By adjusting the number of glucoses attached to these nano-baits, the energy required for their excitation and light response can be adjusted. These nano-baits are a viable alternative to radioactive materials for locating cancer cells.

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First theoretical probe for alkynyl bridged thiophene modified coumarin nonlinear optical materials with D-π-A and A-π-D-π-A structures

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s0218863522500084 ◽

2022 ◽

Author(s):

Shanggeng Li ◽

Fanghua Zhu ◽

Yawen Zhou ◽

Jiaming Hu ◽

Jing Li ◽

...

Keyword(s):

Density Functional ◽

Nonlinear Optical ◽

Molecular Design ◽

Energy Levels ◽

Basis Set ◽

Hybrid Functional ◽

Functional Theory ◽

Text Structures ◽

Polar Moment ◽

Vis Spectroscopy

First-principles exploration is very important to molecular design. In this study, geometric structure, intramolecular charge transfer (ICT), energy levels, polar moment, and ultraviolet–visible (UV–Vis) spectroscopy of eight novel and different alkynyl bridged thiophene modified coumarin nonlinear optical molecules with [Formula: see text]-[Formula: see text]-[Formula: see text] and [Formula: see text]-[Formula: see text]-[Formula: see text]-[Formula: see text]-[Formula: see text] structures had been studied by density-functional theory (DFT) calculations within B3LYP hybrid functional using 6-31 [Formula: see text], [Formula: see text] Gaussian type molecular-orbital basis set. This has guiding significance for the design of nonlinear optical molecules and the development of coumarin-based photoelectric molecules.

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Influence of water on the surface of graphene

EPJ Web of Conferences ◽

10.1051/epjconf/201817406002 ◽

2018 ◽

Vol 174 ◽

pp. 06002

Author(s):

Yunus Kaya ◽

Yalçin Kalkan ◽

Rob Veenhof

Keyword(s):

Density Functional Theory ◽

Water Molecule ◽

Density Functional ◽

Theoretical Models ◽

Surface Conductivity ◽

Basis Set ◽

Hybrid Functional ◽

Functional Theory ◽

The Density Functional Theory ◽

Influence Of Water

We have studied how water modifies the surface of graphene and in particular how the surface conductivity of graphene is affected. According to the literature, two types of interactions should be distinguished: physical, where a water molecule remains intact and is located at some distance from the mesh, and chemical, where a water molecule is imbricated in the graphene bond structure. We have developed theoretical models for both types of interactions using the density functional theory (DFT) with the B3LYP hybrid functional combined with the 6-31G(d) basis set. Our calculations show that the surface conductivity of graphene is reduced in the presence of water.

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Spectral characteristics and DFT Study of vanadyl octaethylporphyrin complex

Mediterranean Journal of Chemistry ◽

10.13171/10.13171/mjc8219043008heh ◽

2019 ◽

Vol 8 (2) ◽

pp. 132

Author(s):

Hamza EL HADKI ◽

Mohammed Salah ◽

Abdallah Zrineh ◽

Khadija Marakchi ◽

Hassna Abou El Makarim ◽

...

Keyword(s):

Density Functional ◽

Chemical Reactivity ◽

Spectral Characteristics ◽

Spectroscopic Properties ◽

Basis Set ◽

Hybrid Functional ◽

Functional Theory ◽

Density Analysis ◽

Electron Density Analysis ◽

Made In

The chemistry of vanadyl porphyrins has been explored using vanadyl octaethylporphyrin as a substance in petroleum porphyrins, crude oils and bitumen. The structural, electronic, thermodynamic, spectroscopic properties are described. The geometry’s optimization of this molecule was done by Density Functional Theory (DFT) using the hybrid Beck three-parameter hybrid functional combined with Lee-Yang-Parr correlation functional (B3LYP) and 6-31G(d) standard basis set. All calculations have been made in the gas phase and in different solvents: benzene, benzonitrile, tetrachloromethane and chloroform. The calculated infrared spectrum was compared with experimental spectroscopic data, and the vibrational assignment was provided. An electron density analysis in terms of natural bond orbitals was conducted to determine the nature of the bonds between the vanadium and nitrogen atoms. The spatial representation of the associated molecular orbitals helped to explain the formation of the V-N bonds and to interpret the chemical reactivity of the compound studied. The electrostatic potential was calculated in order to investigate the reaction properties of the molecule.

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Experimental and DFT studies on the structural and optical properties of chitosan/polyvinyle pyrrolidone/ZnS nano composites

10.21203/rs.3.rs-331123/v1 ◽

2021 ◽

Author(s):

A. M. Abdelghany ◽

M.A. Aboelwafa ◽

M.S. Meikhail ◽

A Oraby

Keyword(s):

Experimental Data ◽

Density Functional ◽

Energy Gap ◽

Basis Set ◽

Hybrid Functional ◽

Indirect Transition ◽

Optical Energy Gap ◽

Functional Theory ◽

Infrared Measurements ◽

Potential Basis

Abstract Chitosan/ Polyvinyl pyrrolidone (CS/PVP) semi-natural polymeric blend involving gradient concentrations of ZnS nanoparticles (ZnS-NPS) was prepared via a simple casting method. In conjunction with computational density functional theory approaches (DFT), prepared samples were characterized by UV/Vis spectrophotometric studies and Fourier transform infrared measurements (FTIR) to take into account a detailed description of the different reaction mechanisms within the polymeric matrices. To conduct all calculations, the Becke three-parameter hybrid functional (B3LYP) correlation function used with the electron core potential basis set LANL2DZ was used. A detailed study for different reaction regimes was studied and reaction via Oxygen was observed to be preferred and compatible with that of the experimental data. UV/vis. Absorption experimental data were used to calculate the optical energy gap using the Mott-Davis equation and observed data was found to follow an indirect transition route.

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14N NQR Study of Urea and Thiourea

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.774-776.757 ◽

2013 ◽

Vol 774-776 ◽

pp. 757-762

Author(s):

Xue Yi Huang ◽

Geng Guang Xu ◽

Feng Long Hao

Keyword(s):

Density Functional ◽

Spectroscopic Technique ◽

Basis Set ◽

Hybrid Functional ◽

Detection Mechanism ◽

Functional Theory ◽

The Density Functional Theory ◽

Quadrupole Resonance ◽

Nuclear Quadrupole ◽

Relative Errors

Nuclear quadrupole resonance (NQR) is a newly developed branch of radio frequency (RF) spectroscopic technique, allowing the detection of many substances containing quadrupole nuclei, such as14N and35Cl, widely existing in explosives and narcotics respectively. In this paper, we focus on the research of its detection mechanism for14N in urea and thiourea. Based on the Density Functional Theory (DFT), employing Beckes three-parameter hybrid functional combined with Lee-Yang-Parr correlation functional (B3LYP), with 6-311++G(d,p) basis set, we have obtained the quantum chemical calculations by using Gaussian 09. Furthermore, experimental results and some discussions related are also presented. At last, we find that the absolute values of relative errors of NQR frequencies are all less than 2%, which indicates that this study is reasonable.

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Molecular orbital analysis of selected organic p-type and n-type conducting small molecules

Acta Chimica Slovaca ◽

10.1515/acs-2017-0002 ◽

2017 ◽

Vol 10 (1) ◽

pp. 6-16

Author(s):

Denisa Cagardová ◽

Vladimír Lukeš

Keyword(s):

Small Molecules ◽

Density Functional ◽

Basis Set ◽

Hybrid Functional ◽

Electronic Band ◽

Functional Theory ◽

Reorganization Energies ◽

Molecular Orbital Analysis ◽

P Type ◽

Orbital Analysis

Abstract In this article, the selected series of commercially available p-type and n-type semiconducting small molecules are systematically studied by density functional theory using the B3LYP hybrid functional and 6-311G(2d,p) basis set. The optimal geometries of each molecule in the electronic neutral and corresponding charged states are calculated. The evaluated energies of frontier molecular orbitals and electronic band gaps are mutually compared together with adiabatic electronic intramolecular reorganization energies. The chemical accuracy of the evaluated theoretical quantities is estimated from the comparison with available experimental data.

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Spectral characteristics and DFT Study of vanadyl octaethylporphyrin complex

Mediterranean Journal of Chemistry ◽

10.13171/mjc8219043008heh ◽

2019 ◽

Vol 8 (2) ◽

pp. 132-139

Author(s):

Hamza EL Hadki ◽

Mohammed Salah ◽

Abdallah Zrineh ◽

Khadija Marakchi ◽

Hassna Abou El Makarim ◽

...

Keyword(s):

Density Functional ◽

Chemical Reactivity ◽

Spectral Characteristics ◽

Spectroscopic Properties ◽

Basis Set ◽

Hybrid Functional ◽

Functional Theory ◽

Density Analysis ◽

Electron Density Analysis ◽

Made In

The chemistry of vanadyl porphyrins has been explored using vanadyl octaethylporphyrin as a substance in petroleum porphyrins, crude oils and bitumen. The structural, electronic, thermodynamic, spectroscopic properties are described. The geometry’s optimization of this molecule was done by Density Functional Theory (DFT) using the hybrid Beck three-parameter hybrid functional combined with Lee-Yang-Parr correlation functional (B3LYP) and 6-31G(d) standard basis set. All calculations have been made in the gas phase and in different solvents: benzene, benzonitrile, tetrachloromethane and chloroform. The calculated infrared spectrum was compared with experimental spectroscopic data, and the vibrational assignment was provided. An electron density analysis in terms of natural bond orbitals was conducted to determine the nature of the bonds between the vanadium and nitrogen atoms. The spatial representation of the associated molecular orbitals helped to explain the formation of the V-N bonds and to interpret the chemical reactivity of the compound studied. The electrostatic potential was calculated in order to investigate the reaction properties of the molecule.

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Exploring Metastable States in UO2 using Hybrid Functionals and Dynamical Mean Field Theory

Journal of Physics Condensed Matter ◽

10.1088/1361-648x/ac3cf1 ◽

2021 ◽

Author(s):

Laura E Ratcliff ◽

Luigi Genovese ◽

Hyowon Park ◽

Peter B. Littlewood ◽

Alejandro Lopez-Bezanilla

Keyword(s):

Field Theory ◽

First Principles ◽

Density Functional ◽

Atomic Orbital ◽

Mean Field Theory ◽

Mean Field ◽

Basis Set ◽

Dynamical Mean Field Theory ◽

Hybrid Functional ◽

Functional Theory

Abstract A detailed exploration of the f-atomic orbital occupancy space for UO2 is performed using a first principles approach based on density functional theory (DFT), employing a full hybrid functional within a systematic basis set. Specifically, the PBE0 functional is combined with an occupancy biasing scheme implemented in a wavelet-based algorithm which is adapted to large supercells. The results are compared with previous DFT+U calculations reported in the literature, while dynamical mean field theory (DMFT) is also performed to provide a further base for comparison. This work shows that the computational complexity of the energy landscape of a correlated f-electron oxide is much richer than has previously been demonstrated. The resulting calculations provide evidence of the existence of multiple previously unexplored metastable electronic states of UO2, including those with energies which are lower than previously reported ground states.

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Evaluating Transition Metal Barrier Heights with the Latest DFT Exchange–Correlation Functionals – the MOBH35 Benchmark Dataset

10.26434/chemrxiv.7732262.v1 ◽

2019 ◽

Author(s):

Mark Iron ◽

Trevor Janes

Keyword(s):

Transition Metal ◽

Density Functional ◽

Computational Cost ◽

Basis Set ◽

Functional Theory ◽

Exchange Correlation ◽

Barrier Heights ◽

Complete Basis Set ◽

Complete Basis Set Limit ◽

Hybrid Functionals

A new database of transition metal reaction barrier heights – MOBH35 – is presented. Benchmark energies (forward and reverse barriers and reaction energy) are calculated using DLPNO-CCSD(T) extrapolated to the complete basis set limit using a Weizmann1-like scheme. Using these benchmark energies, the performance of a wide selection of density functional theory (DFT) exchange–correlation functionals, including the latest from the Truhlar and Head-Gordon groups, is evaluated. It was found, using the def2-TZVPP basis set, that the ωB97M-V (MAD 1.8 kcal/mol), ωB97X-V (MAD 2.1 kcal/mol) and SCAN0 (MAD 2.1 kcal/mol) hybrid functionals are recommended. The double-hybrid functionals PWPB95 (MAD 1.6 kcal/mol) and B2K-PLYP (MAD 1.8 kcal/mol) did perform slightly better but this has to be balanced by their increased computational cost.

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Benchmark of Simplified Time-Dependent Density Functional Theory for UV-Vis Spectral Properties of Porphyrinoids

10.26434/chemrxiv.9912860 ◽

2019 ◽

Author(s):

Kamal Batra ◽

Stefan Zahn ◽

Thomas Heine

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Large Scale ◽

Absolute Error ◽

Time Dependent ◽

Basis Set ◽

Basis Sets ◽

Functional Theory ◽

Framework Materials ◽

Dependent Density

We thoroughly benchmark time-dependent density- functional theory for the predictive calculation of UV/Vis spectra of porphyrin derivatives. With the aim to provide an approach that is computationally feasible for large-scale applications such as biological systems or molecular framework materials, albeit performing with high accuracy for the Q-bands, we compare the results given by various computational protocols, including basis sets, density-functionals (including gradient corrected local functionals, hybrids, double hybrids and range-separated functionals), and various variants of time-dependent density-functional theory, including the simplified Tamm-Dancoff approximation. An excellent choice for these calculations is the range-separated functional CAM-B3LYP in combination with the simplified Tamm-Dancoff approximation and a basis set of double-ζ quality def2-SVP (mean absolute error [MAE] of ~0.05 eV). This is not surpassed by more expensive approaches, not even by double hybrid functionals, and solely systematic excitation energy scaling slightly improves the results (MAE ~0.04 eV).

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