Theoretical insights into a colorimetric azo-based probe to detect copper ions

DFT calculations indicated that the rotation of the N,N-di(carboxymethyl)amino group around the N–CAr bond by approximately 90°, resulted in a larger HOMO–LUMO energy gap, and led to the observed colour change.

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5-Methyl-1,3-phenylene bis[5-(dimethylamino)naphthalene-1-sulfonate]: crystal structure and DFT calculations

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989019009058 ◽

2019 ◽

Vol 75 (7) ◽

pp. 1079-1083

Author(s):

Tanwawan Duangthongyou ◽

Ramida Rattanakam ◽

Kittipong Chainok ◽

Songwut Suramitr ◽

Thawatchai Tuntulani ◽

...

Keyword(s):

Dft Calculations ◽

Energy Gap ◽

Rotation Axis ◽

Three Dimensional ◽

Hydrogen Atoms ◽

Lumo Energy ◽

Compound C ◽

Dansyl Group ◽

Weak Hydrogen Bonds ◽

Homo Lumo

The title compound, C31H30N2S2O6, possesses crystallographically imposed twofold symmetry with the two C atoms of the central benzene ring and the C atom of its methyl substituent lying on the twofold rotation axis. The two dansyl groups are twisted away from the plane of methylphenyl bridging unit in opposite directions. The three-dimensional arrangement in the crystal is mainly stabilized by weak hydrogen bonds between the sulfonyl oxygen atoms and the hydrogen atoms from the N-methyl groups. Stacking of the dansyl group is not observed. From the DFT calculations, the HOMO–LUMO energy gap was found to be 2.99 eV and indicates n→π* and π→π* transitions within the molecule.

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Anthracene-Based Zwitterion with a Small HOMO‒LUMO Energy Gap

Synthesis ◽

10.1055/a-1543-4018 ◽

2021 ◽

Author(s):

Ayane Kayama ◽

Akihiro Shimizu ◽

Ryo Shintani

Keyword(s):

Electronic Structure ◽

Dft Calculations ◽

Light Absorption ◽

Energy Gap ◽

Redox Properties ◽

Low Energy ◽

Structure And Properties ◽

Lumo Energy ◽

Homo Lumo

We have designed and synthesized an anthracene-based zwitterion, 2-methyl-2-azoniaanthracene-7-olate. The zwitterion shows amphoteric redox properties and low-energy light absorption originating from the small HOMO‒LUMO energy gap of ca. 1.7 eV. DFT calculations show that the combination of replacing the C–H with N+–Me and introducing O− is necessary to alter the electronic structure and properties of anthracene significantly.

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TDDFT study of the UV-vis spectra of subporphyrazines and subphthalocyanines

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424611004154 ◽

2011 ◽

Vol 15 (11n12) ◽

pp. 1220-1230 ◽

Cited By ~ 17

Author(s):

Al Mokhtar Lamsabhi ◽

Manuel Yáñez ◽

Otilia Mó ◽

Cristina Trujillo ◽

Fernando Blanco ◽

...

Keyword(s):

Dft Calculations ◽

Absorption Spectra ◽

Boron Atom ◽

Energy Gap ◽

Red Shift ◽

Lumo Energy ◽

Td Dft ◽

Homo Lumo

The UV-vis spectra of a series of subporphyrazines, SubPz(A,R), and subphthalocyanines, SubPc(A,R) ( A = F, Cl; R = H, F, CH3, C3H7, SCH3, SC2H5 and SPh), where A is the substituent attached to the central boron atom and R is the substituent attached to the periphery of the molecule have been analyzed through the use of TD–DFT calculations in vacuum and using chloroform as a solvent. The absorption spectra depend on both, the characteristics of the substituent attached to the periphery of the molecule and the extension of the π-system on going from SubPz to the SubPc analog. These latter effects lead to a red-shift of both the Q-band and the B-band, although the effect is larger for the former, mainly due to the increase of HOMO–LUMO energy gap on going from the SubPz to the SubPc analog. The effect of the substituents R is more intricate, because the profile of the absorption spectra changes depending on whether both substituents are on the same side (uu or dd) or on opposite sides (ud) of the molecular cone. Since the three conformers are rather close in energy, the observed spectra correspond, very likely, to the sum of the spectra of all of them.

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A p–n fusion strategy to design bipolar organic materials for high-energy-density symmetric batteries

Journal of Materials Chemistry A ◽

10.1039/d1ta02059e ◽

2021 ◽

Author(s):

Jihyeon Kim ◽

Heechan Kim ◽

Sechan Lee ◽

Giyun Kwon ◽

Taewon Kang ◽

...

Keyword(s):

Energy Density ◽

Organic Material ◽

Energy Gap ◽

High Energy ◽

High Energy Density ◽

Lumo Energy ◽

Fusion Strategy ◽

Redox Active ◽

Bipolar Type ◽

Homo Lumo

A new bipolar-type redox-active organic material with a wide HOMO–LUMO energy gap is designed though the ‘p–n fusion’ strategy.

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STRUCTURES, ABSORPTION SPECTRA, AND ELECTRONIC PROPERTIES OF POLYFLUORENE AND ITS DERIVATIVES: A THEORETICAL STUDY

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633606002520 ◽

2006 ◽

Vol 05 (03) ◽

pp. 595-608 ◽

Cited By ~ 13

Author(s):

KRIENGSAK SRIWICHITKAMOL ◽

SONGWUT SURAMITR ◽

POTJAMAN POOLMEE ◽

SUPA HANNONGBUA

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Energy Gap ◽

Level Energy ◽

Excitation Energies ◽

Lumo Energy ◽

Functional Theory ◽

Local Energy Minimum ◽

Pi Systems ◽

Homo Lumo

The structural and energetic properties of polyfluorene and its derivatives were investigated, using quantum chemical calculations. Conformational analysis of bifluorene was performed by using ab initio (HF/6-31G* and MP2/6-31G*) and density functional theory (B3LYP/6-31G*) calculations. The results showed that the local energy minimum of bifluorene lies between the coplanar and perpendicular conformation, and the B3LYP/6-31G* calculations led to the overestimation of the stability of the planar pi systems. The HOMO-LUMO energy differences of fluorene oligomers and its derivatives — 9,9-dihexylfluorene (DHPF), 9,9-dioctylfluorene (PFO), and bis(2-ethylhexyl)fluorene (BEHPF) — were calculated at the B3LYP/6-31G* level. Energy gaps and effective conjugation lengths of the corresponding polymers were obtained by extrapolating HOMO-LUMO energy differences and the lowest excitation energies to infinite chain length. The lowest excitation energies and the maximum absorption wavelength of polyfluorene were also performed, employing the time-dependent density functional theory (TDDFT) and ZINDO methods. The extrapolations, based on TDDFT and ZINDO calculations, agree well with experimental results. These theoretical methods can be useful for the design of new polymeric structures with a reducing energy gap.

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SOLVENT EFFECTS ON THE ELECTRONIC STRUCTURE AND NON-LINEAR OPTICAL PROPERTIES OF PYRENE AND SOME OF ITS DERIVATIVES BASED ON DENSITY FUNCTIONAL THEORY

FUDMA Journal of Sciences ◽

10.33003/fjs-2020-0404-477 ◽

2021 ◽

Vol 4 (4) ◽

pp. 236-251

Author(s):

A. S. Gidado ◽

L. S. Taura ◽

A. Musa

Keyword(s):

Density Functional Theory ◽

Gas Phase ◽

Density Functional ◽

Energy Gap ◽

Chemical Reactivity ◽

Basis Set ◽

Lumo Energy ◽

Functional Theory ◽

Organic Optoelectronic ◽

Homo Lumo

Pyrene (C16H10) is an organic semiconductor which has wide applications in the field of organic electronics suitable for the development of organic light emitting diodes (OLED) and organic photovoltaic cells (OPV). In this work, Density Functional Theory (DFT) using Becke’s three and Lee Yang Parr (B3LYP) functional with basis set 6-311++G(d, p) implemented in Gaussian 03 package was used to compute total energy, bond parameters, HOMO-LUMO energy gap, electron affinity, ionization potential, chemical reactivity descriptors, dipole moment, isotropic polarizability (α), anisotropy of polarizability ( Δ∝) total first order hyper-polarizability () and second order hyperpolarizability (). The molecules used are pyrene, 1-chloropyrene and 4-chloropyrene in gas phase and in five different solvents: benzene, chloroform, acetone, DMSO and water. The results obtained show that solvents and chlorination actually influenced the properties of the molecules. The isolated pyrene in acetone has the largest value of HOMO-LUMO energy gap of and is a bit closer to a previously reported experimental value of and hence is the most stable. Thus, the pyrene molecule has more kinetic stability and can be described as low reactive molecule. The calculated dipole moments are in the order of 4-chloropyrene (1.7645 D) < 1-chloropyrene (1.9663 D) in gas phase. The anisotropy of polarizability ( for pyrene and its derivatives were found to increase with increasing polarity of the solvents. In a nutshell, the molecules will be promising for organic optoelectronic devices based on their computed properties as reported by this work.

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HOMO–LUMO Energy-Gap Tuning of π-Conjugated Zwitterions Composed of Electron-Donating Anion and Electron-Accepting Cation

The Journal of Organic Chemistry ◽

10.1021/acs.joc.0c02343 ◽

2020 ◽

Vol 86 (1) ◽

pp. 770-781

Author(s):

Akihiro Shimizu ◽

Yu Ishizaki ◽

Shun Horiuchi ◽

Takashi Hirose ◽

Kenji Matsuda ◽

...

Keyword(s):

Energy Gap ◽

Lumo Energy ◽

Homo Lumo

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Strategic design of thiophene-fused nickel dithiolene derivatives for efficient NLO response

Physical Chemistry Chemical Physics ◽

10.1039/c8cp01592a ◽

2018 ◽

Vol 20 (28) ◽

pp. 19007-19016 ◽

Cited By ~ 3

Author(s):

Manoj Majumder ◽

Anirban Misra

Keyword(s):

Energy Gap ◽

First Hyperpolarizability ◽

Lumo Energy ◽

Strategic Design ◽

Nlo Response ◽

Acceptor Group ◽

Donor Acceptor ◽

Homo Lumo

The zwitterionic donor–acceptor group significantly reduces the HOMO–LUMO energy gap resulting in an enormous increase in the first hyperpolarizability values.

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