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Narissa Kanlayakan

Other affiliations: Western Washington University
Bio: Narissa Kanlayakan is an academic researcher from Chiang Mai University. The author has contributed to research in topics: Intramolecular force & Tautomer. The author has an hindex of 3, co-authored 5 publications receiving 57 citations. Previous affiliations of Narissa Kanlayakan include Western Washington University.

Papers
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Journal ArticleDOI
TL;DR: In this paper, the effect of proton donors, namely NH-type and OH-type, on the excited-state intramolecular proton transfer (ESIPT) of hydrogen-bonding (H-bond) molecules was investigated using density functional theory (DFT) and time-dependent DFT at the B3LYP level with the TZVP basis set.
Abstract: The effect of proton donors, namely NH-type and OH-type, on the excited-state intramolecular proton transfer (ESIPT) of hydrogen-bonding (H-bond) molecules was investigated using density functional theory (DFT) and time-dependent DFT (TD-DFT) at the B3LYP level with the TZVP basis set. The important parameters for bond distances involved in the intramolecular H-bond revealed that H-bonds of OH-type are stronger than those of NH-type and this was supported by the greater red-shift of O–H vibrational modes in the excited-state. The potential energy surfaces along the proton transfer (PT) reaction show that the ESIPT of O–H type occurs with a small barrier or barrierless in the excited-state whereas those of N–H type have higher PT barriers except for the one with a stronger proton acceptor, resulting in a smaller barrier. On-the-fly dynamic simulations on the first excited-state were further carried out to provide the important dynamic information on PT time and probability. The results of dynamic simulations are in accordance with the potential energy surfaces in which the N–H type shows no PT in APBT but slow PT in APBI and fast PT in HNHPIP, while the O–H type (HBI, HBT and HPIP) exhibits ultrafast PT within 80 fs. Moreover, the occurrence of the ESIPT process is strongly dependent on reaction energy and activation energy, in which the H-bond molecules with thermodynamically and kinetically favorable characters always provide the ESIPT. Therefore, the type of proton donor and proton acceptor of H-bond molecules is very important to hinder or effectively facilitate the ESIPT process.

40 citations

Journal ArticleDOI
TL;DR: The results revealed that the excited-state intermolecular proton transfer for HBI is fast, whereas the excited/substantial proton transfers with protic solvents are slower than that of HBI because the competition between intra- and intermolescular hydrogen-bonds hinder the formation of tautomer, hence explaining the low quantum yield found in the protic solvent experiment.
Abstract: Excited-state proton transfer (ESPT) processes of 2-(2′-hydroxyphenyl)benzimidazole (HBI) and its complexation with protic solvents (H2O, CH3OH, and NH3) have been investigated by both static calculations and dynamics simulations using density functional theory (DFT) at B3LYP/TZVP theoretical level for ground state (S0) and time-dependent (TD)-DFT at TD-B3LYP/TZVP for excited state (S1). For static calculations, absorption and emission spectra, infrared (IR) vibrational spectra of O–H mode, frontier molecular orbitals (MOs), and potential energy curves (PECs) of proton transfer coordinate were analyzed. Simulated absorption and emission spectra show an agreement with available experimental data. The hydrogen bond strengthening in the S1 state has been proved by the changes of IR vibrational spectra and bond parameters of the hydrogen moiety with those of the S0 state. The MOs provide the visual electron density redistribution confirming the hydrogen bond strengthening mechanism. The PECs show that the pro...

30 citations

Journal ArticleDOI
TL;DR: In this article, the electronic properties of the NH-type hydrogen bonding molecules (APBI, APBO, APBT, and APIP) and their derivatives have been theoretically investigated.

19 citations

Journal ArticleDOI
TL;DR: In this paper, a molecular screening has been carried out for fluorescent probes harnessing excited-stated intramolecular proton transfer (ESIPT) of NH-type molecules having aminophenyl or tosylaminyl as a proton donor with different substituents using time-dependent density functional theory.
Abstract: A molecular screening has been carried out for fluorescent probes harnessing excited-stated intramolecular proton transfer (ESIPT) of NH-type molecules having aminophenyl or tosylaminophenyl as a proton donor and benzimidazole, benzoxazole, benzothiazole, or imidazo[1,2-a]pyridine as a proton acceptor with different substituents using time-dependent density functional theory. Among the designed ESIPT molecules, 2-(2′-tosylaminophenyl)benzimidazole, 2-(2′-tosylaminophenyl)benzothiazole, and 2-(2′-tosylaminophenyl)imidazo[1,2-a]pyridine with dimethylamino in the tosylaminophenyl and/or cyano in the benzimidazole, benzothiazole, and imidazo[1,2-a]pyridine, respectively, were revealed to be the best five candidates because they passed the screening requirements, including photophysical, kinetics, and thermodynamic parameters. Here, these five candidates required less photo-absorption around 380 nm and emitted the tautomer peaks in the near infrared (NIR) region, leading to large Stokes shifts (∼200 nm) with no self-reabsorption, which are important characteristics for fluorescent probes. The NIR emission is caused by the intramolecular charge-transfer character of the strong electron-donating dimethylamino in the tosylaminophenyl moiety and heteroatoms in the benzimidazole/benzothiazole/imidazo[1,2-a]pyridine moiety as evidenced by the electron-density differences and frontier molecular orbitals. In addition, they exhibit high photo-acidity and photo-basicity (low PT barrier with highly exothermic) to warrantee the ESIPT. Therefore, the obtained screening information in this work could be beneficial for designing new ESIPT fluorescent-based probes.

6 citations

Journal ArticleDOI
09 Sep 2021-Chem
TL;DR: In this article, a topology-directed polycondensation of conventional p-type knots with n-type isoindigo linkers was proposed to form non-conjugated tetragonal and hexagonal two-dimensional polymeric frameworks.

Cited by
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01 Feb 1995
TL;DR: In this paper, the unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio using DFT, MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set.
Abstract: : The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

1,652 citations

Journal Article
TL;DR: The research expands the understanding of the nature of hydrogen bonding by delineating the interaction between hydrogen bonds and photons, thereby providing a basis for excited-state hydrogen bonding studies in photophysics, photochemistry, and photobiology.
Abstract: Because of its fundamental importance in many branches of science, hydrogen bonding is a subject of intense contemporary research interest. The physical and chemical properties of hydrogen bonds in the ground state have been widely studied both experimentally and theoretically by chemists, physicists, and biologists. However, hydrogen bonding in the electronic excited state, which plays an important role in many photophysical processes and photochemical reactions, has scarcely been investigated.Upon electronic excitation of hydrogen-bonded systems by light, the hydrogen donor and acceptor molecules must reorganize in the electronic excited state because of the significant charge distribution difference between the different electronic states. The electronic excited-state hydrogen-bonding dynamics, which are predominantly determined by the vibrational motions of the hydrogen donor and acceptor groups, generally occur on ultrafast time scales of hundreds of femtoseconds. As a result, state-of-the-art femtos...

886 citations

Journal ArticleDOI
TL;DR: Instrumental techniques and methodologies currently used for the determination of particular structural parameters were summarized and the influence of those parameters as well as the role of hydrogen bonding on basic mechanical properties of dimethacrylate polymer networks were demonstrated.
Abstract: Material characterization by the determination of relationships between structure and properties at different scales is essential for contemporary material engineering. This review article provides a summary of such studies on dimethacrylate polymer networks. These polymers serve as photocuring organic matrices in the composite dental restorative materials. The polymer network structure was discussed from the perspective of the following three aspects: the chemical structure, molecular structure (characterized by the degree of conversion and crosslink density (chemical as well as physical)), and supramolecular structure (characterized by the microgel agglomerate dimensions). Instrumental techniques and methodologies currently used for the determination of particular structural parameters were summarized. The influence of those parameters as well as the role of hydrogen bonding on basic mechanical properties of dimethacrylate polymer networks were finally demonstrated. Mechanical strength, modulus of elasticity, hardness, and impact resistance were discussed. The issue of the relationship between chemical structure and water sorption was also addressed.

82 citations

Journal ArticleDOI
TL;DR: In this paper, the effect of intermolecular hydrogen bonding induced by protic solvents on the excited state proton transfer (ESPT) reaction of 3-hydroxyflavone (3HF) was theoretically investigated using density functional theory (DFT) and time-dependent DFT (TD-DFT).

35 citations

Journal ArticleDOI
TL;DR: In this paper, the authors discuss the recent significant achievements made in the field of white light emission applying pure organic molecules, and discuss how to achieve efficient white light emissions in solution, as well as, solid state.

33 citations