Search results for "LUMO"

Protection Motivation Theory in Information Systems Security Research

2021

Protection motivation theory (PMT) is one of the most commonly used theories to examine information security behaviors. Our systematic review of the application of PMT in information systems (IS) security and the comparison with its application for decades in psychology identified five categories of important issues that have not yet been examined in IS security research. Discussing these issues in terms of why they are relevant and important for IS security, and to what extent IS research has not considered them, offers new research opportunities associated with the study of PMT and IS security threats. We suggest how future studies can approach each of the open issues to provide a new roa…

2017

The energy levels of the HOMO/LUMO Frontier orbitals and the electronic properties of phthalocyanine macrocycles can be tuned by the introduction of substituents. Starting from tetrafluorophthalonitrile, we studied the substitution of fluorine atoms by (2-thienyl)ethoxy moieties. An optimization of the experimental conditions (nature and stoichiometry of the alcohol and base, temperature) allowed us to obtain the monoalkoxy derivative with a very good yield. It was fully characterized using 19F and 1H NMR spectroscopies, thermal analysis and X-ray diffraction on single crystals. Then, the corresponding zinc phthalocyanine was synthesized, characterized by means of 19F and 1H NMR spectroscop…

Uptake of organic xenobiotics by benthic invertebrates from sediment contaminated by the pulp and paper industry

2007

Abstract Uptake of pulp and paper mill-derived pollutants by benthic invertebrates from sediment in Southern Lake Saimaa, eastern Finland, was studied. Two groups of benthic invertebrates (Diptera and Oligochaeta) were analyzed for their concentrations of resin acids (RAs), chlorophenolics (CPs) and β -sitosterol. The samples were collected 1 and 3 km downstream from the mill. In laboratory experiments Chironomus plumosus (a dipteran) and Lumbriculus variegatus (oligochaete) were exposed for 14 d to sediments collected from the same locations. The concentrations of RAs, CPs and β -sitosterol were higher in the areas downstream from the mill than those in the upstream reference area in both …

Crystal structure and theoretical study of (2E)-1-[4-hydroxy-3-(morpholin-4-ylmethyl)phenyl]-3-(thiophen-2-yl)prop-2-en-1-one

2018

WOS: 000437492100018

Solvent impact on the planarity and aromaticity of free and monohydrated zinc phthalocyanine: a theoretical study

2017

A theoretical investigation on the planarity of molecular structure of zinc phthalocyanine (ZnPc) and its aromaticity has been performed using B3LYP and M06-2X density functionals combined with selected Pople-type basis sets. The effect of the applied calculation method on the optimized structure of ZnPc and ZnPc∙∙∙H2O, both in the gas phase and in the polar solvent, was analyzed. To quantify the aromaticity of the ZnPc and ZnPc∙∙∙H2O complexes, both the geometric and magnetic criteria, i.e., Harmonic Oscillator Model of Aromaticity (HOMA) index and the nucleus-independent chemical shift (NICS) values at the centers or 1 A above the centers of structural subunits, were calculated. The energ…

Rola efektu podstawnikowego w chemii i naukach pokrewnych

2017

Zmiany struktury π-elektronowej pierścieniowych układów aromatycznych wywołane obecnością podstawników, stanowią ważne zagadnienie w dziedzinie chemii strukturalnej. Ma to swoje źródło w tzw. efekcie podstawnikowym, który w znacznym stopniu decyduje o reaktywności związków aromatycznych, jak również o innych właściwościach chemicznych, biologicznych i fizycznych. Efekt podstawnikowy jest terminem bardzo często używanym w literaturze chemicznej i pokrewnej, statystycznie każdego dnia pojawia się ponad 10 prac, w których pojęcie to występuje w tytule artykułu lub abstrakcie. Badania efektu podstawnikowego mają na celu poznanie wzajemnych interakcji pomiędzy podstawnikami przyłączonymi do pier…

Design Features for Gender-specific Differences in Blended Learning within Higher Education in Indonesia

2019

Blended learning offers learning solutions for higher educational institutions facing the industrial revolution 4.0. In this study, we investigated the influence factors student perceptions of blended learning based on gender-specific differences in Indonesia. We applied a research model to systematically assess the effect of design features on the effectiveness of blended learning indicators (intrinsic motivation and student satisfaction). Moreover, we evaluated the research model for both genders separately. Based on the quantitative survey of 223 Indonesian students, our study confirms that the design features significantly influence the effectiveness of blended learning for male and fem…

New Internal-Charge-Transfer Second-Order Nonlinear Optical Chromophores Based on the Donor Ferrocenylpyrazole Moiety

2016

A series of new N-arylated ferrocenepyrazole structures, carrying different donor or acceptor substituents in the para position of the aryl ring, has been synthesized by the Chan-Lam cross-coupling reaction. The nonplanar geometric molecular structure of some of these chromophores together with their crystal packing was determined by X-ray diffraction, and the HOMO and LUMO energy levels were evaluated by electrochemical and optical measurements and by density functional theoretical (DFT) calculations. By the investigation of solvent effects and time-dependent DFT (TD-DFT) calculations, the intense electronic absorption band around 270-310 nm was confirmed to be an internal-chargetransfer (…

Understanding C C bond formation in polar reactions. An ELF analysis of the Friedel Crafts reaction between indoles and nitroolefins

2013

[EN] The Friedel-Crafts (FC) reaction of N-methyl indole 1 with nitroethylene 2 has been studied using DFT methods at the B3LYP/6-31+G** level in order to characterize the bonding changes along the C-C bond-formation process in polar reactions. For this FC reaction a two-step mechanism has been found. The first step is associated with the C-C bond formation between the most electrophilic centre of nitroethylene and the most nucleophilic centre of N-methyl indole, to yield a zwitterionic intermediate IN. The second step corresponds to an intramolecular proton transfer process at IN, regenerating the aromatic system present at the indole. Despite the high electrophilic character shown by nitr…

Emission energy of azole-based ionic iridium(III) complexes: a theoretical study.

2014

A theoretical density functional theory study has been performed on different families of cationic cyclometallated Ir(III) complexes with the general formula [Ir(C^N)2(N^N)](+) and azole-based ligands. The goal was to investigate the effect that the number and position of the nitrogen atoms of the azole ring have on the electronic structure and emission wavelength of the complex. The increase in the number of nitrogen atoms changes the relative energy of the HOMO and LUMO levels and leads to a gradual shift in the emission wavelength that can be larger than 100 nm. The direction of the shift however depends on the ligand in which the azole ring is introduced. The emission shifts to bluer wa…