DFT calculations on polarizabilities and hyperpolarizabilities for the neutral and anionic yttrium oxide clusters

2015 ◽  
Vol 14 (07) ◽  
pp. 1550049 ◽  
Author(s):  
Ambigapathy Suvitha ◽  
Natarajan Sathiyamoorthy Venkataramanan
Keyword(s):  
Quantum Chemical ◽  
Dipole Moments ◽  
Small Variation ◽  
Chemical Hardness ◽  
High Symmetry ◽  
Polarizability Anisotropy ◽  
First Hyperpolarizability ◽  
Anionic Clusters ◽  
Electronic Delocalization ◽  
Hardness Values

The electronic properties, polarizabilities, first and second hyperpolarizabilities of YOn clusters of [Formula: see text]–12 were studied using the quantum chemical method. The vertical ionization potential (VIP) values for the anionic clusters increase monotonically with the cluster size. Among the neutral clusters YO3 and YO8 have the least chemical hardness values, where in anionic clusters with size [Formula: see text] possesses the least chemical hardness. Anionic clusters have more electrons attracting tendency than the neutral clusters. The computed static mean polarizability of neutral yttrium oxides has positive values but is close to zero. The incorporation of oxygen atom quenches the polarizability of yttrium. The computed polarizability anisotropy of neutral clusters shows an oscillatory effect both at static and at dynamic conditions. The first hyperpolarizability for many YOn clusters are close to zero. The existence of high symmetry in these clusters reduces the first hyperpolarizability values which was supported by the small dipole moments. The computed [Formula: see text] values for the static neutral and anionic clusters show only a small variation. The decrease in the polarizability and second hyperpolarizability with size can be interpreted in terms of the electronic delocalization and chemical bonding in the clusters.

Dipole moments and quantum chemical study of the structure of furan-containing gem-bromonitroethenes

2015 ◽  
Vol 51 (9) ◽  
pp. 1282-1285
Author(s):  
Ya. A. Vereshchagina ◽  
D. V. Chachkov ◽  
R. R. Khanafieva ◽  
A. Z. Alimova ◽  
V. M. Berestovitskaya ◽  
...  
Keyword(s):  
Quantum Chemical ◽  
Dipole Moments ◽  
Quantum Chemical Study ◽  
Chemical Study

Synthesis and DFT Studies of Pyrimidin-1(2H)-ylaminofumarate Derivatives

2020 ◽  
Vol 42 (5) ◽  
pp. 746-746
Author(s):  
Murat Saracoglu Murat Saracoglu ◽  
Zulbiye Kokbudak Zulbiye Kokbudak ◽  
M Izzettin Yilmazer and Fatma Kandemirli M Izzettin Yilmazer and Fatma Kandemirli
Keyword(s):  
Quantum Chemical ◽  
Energy Gap ◽  
Basis Set ◽  
Chemical Hardness ◽  
Pyrimidine Derivatives ◽  
1H And 13C Nmr ◽  
Solvent Phase ◽  
B3lyp Method ◽  
Ft Ir ◽  
New Compounds

Pyrimidine derivatives have biological and pharmacological properties. Therefore, in this study we focused on the synthesis various Pyrimidine derivatives to make noteworthy contributions this class of heterocyclic compounds. In the present study, the new compounds (4-6) were obtained by the reactions of 1-amino-5-benzoyl-4-phenylpyrimidin-2(1H)-one (1), 1-amino-5-(4-methylbenzoyl)-4-(4-methylphenyl)pyrimidin-2(1H)-one (2) and 1-amino-5-(4-methoxybenzoyl)-4-(4-methoxyphenyl)pyrimidin-2(1H)-one (3) with dimethyl acetylenedicarboxylate. The structures of these compounds were proved by elemental analysis, FT-IR, 1H and 13C-NMR spectra. In addition to, quantum chemical calculations were made to find molecular properties of the pyrimidin-1(2H)-ylaminofumarate derivatives (4-6) by using DFT/B3LYP method with 6-311++G(2d,2p) basis set. Quantum chemical features such as EHOMO, ELUMO, energy gap, ionization potential, chemical hardness, chemical softness, electronegativity etc. values for gas and solvent phase of neutral molecules were calculated and discussed.

Computational Study of Adsorption Effects of Karanjin Drug Over Carbon Nanotube (C56H16) as Factor of Drug Delivery System — A Quantum Chemical Approach

NANO ◽  
2021 ◽  
pp. 2150106
Author(s):  
Anoop Kumar Pandey ◽  
Vijay Singh ◽  
Apoorva Dwivedi
Keyword(s):  
Drug Delivery ◽  
Carbon Nanotube ◽  
Gas Phase ◽  
Drug Delivery System ◽  
Delivery System ◽  
Quantum Chemical ◽  
Density Functional ◽  
Computational Study ◽  
Chemical Hardness ◽  
Adsorption Effect

Karanjin, phytochemical from Pongamia pinnata is reported to be effective against HIV that causes AIDS in humans, however, the delivery of this therapeutic molecule still needs improvement. Hence, this study provides a better understanding of the nonbonded interaction between an anti-HIV drug karanjin and carbon nanotube (CNT) (C56H16). The electronic structure and interaction properties of the molecule karanjin over the surface of CNT were theoretically studied in the gas phase by DFT/B3LYP/6-31G ([Formula: see text]) level of theory for the first time. The UV–Vis spectra and transitions of the karanjin drug, CNT (C56H16) and complex CNT (C-56)/karanjin in gas phase have been calculated by time-dependent density functional theory (TDDFT) for the investigation of adsorption effect. To support our hypothesis, we have performed quantum chemical analysis for CNT (C56H16)/karanjin in water and DMSO solvent. In this process, this CNT (C-56)/karanjin complex enters into affected cell in liquid medium. After that, the drug delivery system CNT (C-56) unloads karanjin at the affected site. The binding character interactive species have been determined by NBO and AIM analysis. The frontier orbital HOMO–LUMO gap, chemical softness, chemical hardness have also been calculated to understand its complete chemical properties. The outcomes from our interaction of drug karanjin with CNT (C56H16) will be instrumental for better drug delivery potential in the upcoming future.

Commonality in the Origin and the Manifestation in the Real World of Electronegativity and Hardness

2012 ◽  
pp. 76-102
Author(s):  
Nazmul Islam ◽  
Dulal C. Ghosh
Keyword(s):  
Real World ◽  
General Principle ◽  
Comparative Studies ◽  
Dipole Moments ◽  
Fundamental Property ◽  
Chemical Hardness ◽  
The Real ◽  
Atoms And Molecules ◽  
Electronegativity Equalization ◽  
The One

The electronegativity and the hardness are two different fundamental descriptors of atoms and molecules, and this chapter describes how the authors have logistically discovered the commonality between the heuristic and basic philosophical structures of their origin and also the manifestation in the real world. Also, the chapter demonstrates that the physical hardness and the chemical hardness with evolution of time have converged to one and the same general principle– the hardness. The authors also try to expose the physical basis and operational significance of another very important descriptor–the electronegativity. The chapter also explores whether the hardness equalization principle can be conceived analogous to the well established electronegativity equalization principle. The authors hypothesize that the electronegativity and the absolute hardness are two different appearances of the one and the same fundamental property of atoms, and the Hardness Equalization Principle can be equally conceived like the electronegativity equalization principle. To test this hypothesis, the authors have made several comparative studies by evaluating some well known chemico-physical descriptors of the real world, such as hetero nuclear bond distances, dipole charges, and dipole moments of molecules. The detailed comparative study suggests that the paradigm of the hardness equalization principle may be another law of nature like the established electronegativity equalization principle.

scholarly journals Calculating transition dipole moments of phosphorescent emitters for efficient organic light-emitting diodes

2019 ◽  
Vol 21 (19) ◽  
pp. 9740-9746
Author(s):  
Mohammad Babazadeh ◽  
Paul L. Burn ◽  
David M. Huang
Keyword(s):  
Dipole Moment ◽  
Quantum Chemical ◽  
Dipole Moments ◽  
Molecular Geometry ◽  
Transition Dipole Moment ◽  
Organic Light Emitting Diodes ◽  
Transition Dipole ◽  
Light Emitting ◽  
Organic Light ◽  
Transition Dipole Moments

Quantum-chemical calculations show that the direction of the transition dipole moment of organometallic phosphorescent emitters is sensitive to molecular geometry.

Influence of the Chemical Structure on the Luminescence Properties of Organic Dye Molecules

1999 ◽  
Vol 598 ◽  
Author(s):  
Egbert Zojer ◽  
Ulrich Rant ◽  
Petra Buchacher ◽  
Ruth Müllner ◽  
Franz Stelzer ◽  
...  
Keyword(s):  
Configuration Interaction ◽  
Quantum Chemical ◽  
Dipole Moments ◽  
Experimental Investigations ◽  
Electron Configuration ◽  
Dye Molecules ◽  
Interaction Technique ◽  
Transition Dipole ◽  
Singlet Exciton ◽  
Exciton Localization

ABSTRACTIn this contribution we compare experimental investigations (of photoluminescence, absorption and modulation spectroscopy) for a number of novel dye molecules to quantum-chemical simulations. The investigated materials contain phenylene-, phenylenevinylene-, naphthylene- and anthrylene units linked either by saturated or non saturated bonds. In the first part of the paper we give a short overview of the principal optical properties of the investigated molecules including a discussion of exciton localization effects. The latter can be accomplished by studying the geometry modifications in the excited state relative to the ground state. To do so, we couple the Austin Model 1 (AM1) approach to a multi-electron configuration interaction technique (MECI). The optical spectra are subsequently obtained from the Intermediate Neglect of Differential Overlap (INDO) Hamiltonian combined with a Single Configuration Interaction (SCI) approach. In the main section of this contribution we show the results of singlet exciton lifetime measurements performed with a modulation technique. An excellent agreement was found between the experimental data and quantum-chemical simulations for the transition dipole moments

The Electronic and Non-linear Optical Properties of Oxo-titanium Phthalocyanines

1999 ◽  
Vol 03 (05) ◽  
pp. 331-338 ◽  
Author(s):  
FRYAD HENARI ◽  
ANDREW DAVEY ◽  
WERNER BLAU ◽  
P. HAISCH ◽  
M. HANACK
Keyword(s):  
Optical Properties ◽  
Electronic Properties ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Dipole Moments ◽  
Non Linear ◽  
Linear Behaviour ◽  
Linear Optical Properties ◽  
Linear Optical ◽  
Semiempirical Quantum Chemical Calculations

The valence electronic properties of some unsubstituted and peripherally substituted oxo-titanium phthalocyanines are reported. Semiempirical quantum chemical calculations show that the nature of peripheral substituents has a strong bearing on the valence electronic properties, including the state dipole moments and absorption wavelength. The non-linear optical response was measured around the the Q-band resonance. The effect of different substituents and substitution patterns on the non-linear behaviour of the samples was determined. The combined results suggest that tuning of electronic and optical properties is effectively achieved by functionalization of the edges of the conjugated ring.

Quantum chemical computations on rotational isomers of hydrogen nitrite and nitritomethane

1982 ◽  
Vol 381 (1781) ◽  
pp. 443-455 ◽  
Keyword(s):  
Excited States ◽  
Quantum Chemical ◽  
Dipole Moments ◽  
Basis Set ◽  
Electronic Transitions ◽  
Rotational Isomers ◽  
Transition Structures ◽  
Quantum Chemical Computations ◽  
Split Valence ◽  
Good Agreement

Ab initio molecular-orbital computations with a split-valence 4-31G basis set have been carried out on syn- and antiperiplanar conformers of both HONO and H 3 CONO, and on the transition structures in the unimolecular isomerization process. Calculated values of geometric structural and rotational parameters, dipole moments, wavenumbers of vibrational transitions, energies of vertical electronic transitions to both neutral and ionized excited states, and thermodynamic properties are compared with experimental data; generally good agreement is found. No explanation of the anomalous stability of antiperiplanar HONO has been discovered.

Sign in / Sign up

Export Citation Format

Share Document