Calculation of ionization potential and chemical hardness: A comparative study of different methods

The non‐linear and linear optical properties of 2‐napthol based four monoazo dyes were examined by computational and Z‐scan methods. Time‐dependent (TD)‐density functional theory (DFT) computations were used to evaluate the linear polarizability (α), first‐order hyperpolarizability (β) and second‐order hyperpolarizability (γ) using global hybrid and range separated hybrid functionals at 6–311+ G (d) basis set. The functional, ωB97 performed better in the determination of linear polarizability (α) and ωB97X−D performed better in the determination of the first‐order hyperpolarizability (β) and second‐order hyperpolarizability (γ) among the global hybrid and range separated hybrid functionals. To support our theoretical findings for α, β, and γ, we have correlated with the Hammett‐coefficient (σ), excited state coefficient (σex) as well as by hyper‐hardness (Γ) relations. Third order NLO parameters – non‐linear refractive index (η2), non‐linear absorption coefficient (β), real parts and the imaginary parts of third order susceptibility (χ(3)), and second order hyperpolarizability (γ) were investigated by close and open aperture methods using Z‐scan technique. The –NO2 substituted dye 2 shows higher value of molecular susceptibility (χ(3)), polarizability (α), and hyperpolarizability (β, γ) parameters among the studied azo dyes. They are likely to have potential applications in optoelectronics and photonics.

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“…By using Koopmans theorem, the ionization potential and electron affinity are calculated as,

true μ = \frac{E_{L U M O + E_{H O M O}}}{2}

true η = \frac{E_{L U M O - E_{H O M O}}}{2}

…”

Section: Resultsmentioning

confidence: 99%

“…h ¼ ðIP À EAÞ 2 (4) where, IP and EA are ioniztion potential and electron affinity respectively. By using Koopmans theorem, [113] the ionization potential and electron affinity are calculated as,…”

Section: Frontier Molecular Orbital (Fmo) and Molecular Electrostaticmentioning

confidence: 99%

NLO Properties of 2‐Napthol Monoazo Disperse Dyes by DFT and Z‐Scan Technique – A Detailed Study

Yadav

Sreenath²,

Chitrambalam³

et al. 2019

ChemistrySelect

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“…Therefore, a new parameter for the hydrogen atom needs to be derived that corresponds to the 6c parameter in Equation 16 in order to permit calculation of chemical hardnesses of molecules containing hydrogen atoms.…”

Section: Theoretical Methodsmentioning

confidence: 99%

“…Koopman's theorem [15,16] provides an alternative molecular orbital theory method to calculate the ionization energies and electron affinities of molecules. According to this theorem, the negative of the highest occupied molecular orbital energy and the negative of the lowest unoccupied molecular orbital energy correspond to ionization energy and electron affinity, respectively (-E HOMO = IE and -E LUMO = EA).…”

Section: Introductionmentioning

confidence: 99%

A new method for calculation of molecular hardness: A theoretical study

Kaya

2015

Computational and Theoretical Chemistry

119

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“…For better understanding the relationship of reactivity of molecules with their nonlinear optical properties, the global relativity descriptors such as hardness ( η ), electrophilicity index ( ω ), electronegativity ( χ ), and the softness (S) were theoretical evaluated by using HOMO‐LUMO energy gap Table . “Electrophilicity index (ω)” is used to define photostability for dyes 4a–4d and is defined by electron absorbing capacity of molecule using Equation ,

normalω = \frac{{normalμ}^{2}}{η},

where μ is the “chemical potential” of molecule.…”

Section: Nonlinear Optical (Nlo) Propertiesmentioning

confidence: 99%

Experimental and theoretical investigation of linear and nonlinear optical properties of ethyl‐3‐hydroxy‐2‐napthoate azo dyes by solvatochromic, computational aspects, and Z‐scan technique

Yadav

Taware

Sreenath³

et al. 2020

J of Physical Organic Chem

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To investigate the effect of substituents in azo dyes on their nonlinear optical properties, four azo dyes were synthesized using ethyl‐3‐hydroxy‐2‐naphthoate as a coupler and characterized. The polarizability (α) and hyperpolarizability (β and γ) constants were determined by using solvatochromic and computational method. A group of global hybrid and range seperated hybrid functionals having different Hartree‐Fock exchange percentage were used to evaluate the NLO properties. The functional ωB97 and ωB97XD performed better in the determination of polarizability (α) and hyperpolarizability (β and γ), respectively. The observed results for polarizability and hyperpolarizability parameters were supported by highest occupied molecular orbital‐lowest unoccupied molecular orbital (HOMO‐LUMO) energy gap, Hammett‐coefficient (σ), excited‐state coefficients (σex), and hyper‐hardness (Γ) values. Third‐order NLO properties were analyzed by using Z‐scan technique. The –OCH3 substituted dye 4d shows higher value of molecular susceptibility (χ(3)), polarizability (α), and hyperpolarizability (β and γ) parameters among the studied azo dyes. They are likely to have the potential applications in optoelectronics and photonics.

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Calculation of ionization potential and chemical hardness: A comparative study of different methods

Cited by 70 publications

References 44 publications

NLO Properties of 2‐Napthol Monoazo Disperse Dyes by DFT and Z‐Scan Technique – A Detailed Study

NLO Properties of 2‐Napthol Monoazo Disperse Dyes by DFT and Z‐Scan Technique – A Detailed Study

A new method for calculation of molecular hardness: A theoretical study

Experimental and theoretical investigation of linear and nonlinear optical properties of ethyl‐3‐hydroxy‐2‐napthoate azo dyes by solvatochromic, computational aspects, and Z‐scan technique

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