Exploring the role of quantum chemical descriptors in modeling acute toxicity of diverse chemicals to Daphnia magna

Exploring the role of quantum‐mechanical descriptors in the concentration‐dependent adsorption of aromatic organic compounds by multiwalled carbon nanotubes

“…Besides this, the other quantum‐mechanical descriptors, namely, the absolute electronegativity and electron‐correlation energy were also observed to be significantly correlated with the adsorption coefficients . In several other studies also, our research group have found the importance of dynamic electron correlation in influencing various biological as well as physicochemical properties . In our recent work, such quantum‐mechanical descriptors are also found to be quite reliable in the prediction of adsorption by SWCNTs but which vary with the adsorbate concentration.…”

“…Conversely, the DFT through an XC functional takes care of both exchange and Columbic correlations. Therefore, the electron‐correlation energy and electron‐correlation contribution to the aforementioned descriptors ( D ) can be approximately estimated using: D (CORR) ≈ D (DFT) − D (HF), where D (DFT) is the descriptor computed using the DFT method and D (HF) is that computed using the HF method, as have been successfully employed in our previous works modeling the physicochemical properties and biological activities of environmentally important compounds . Note that all the quantum‐mechanical descriptors and their electron‐correlation contribution were estimated after optimizing the molecular geometry of the compounds (in the dataset described below) at the aforementioned levels of the quantum‐mechanical methods.…”

“…properties. [6,[35][36][37][38][39][40][41][42][43] In our recent work, [44] such quantum-mechanical descriptors are also found to be quite reliable in the prediction of adsorption by SWCNTs but which vary with the adsorbate concentration. In continuation of our previous work on the adsorption of organic compounds by MWCNTs at infinite dilute concentration, [6] here, we explore the utility of quantum-chemical descriptors and their electron-correlation, in quantitative prediction of concentration-dependent adsorption of aromatic organic compounds by MWCNTs at five different adsorbate concentrations while comparing their reliability with the adsorbate descriptors of existing pp-LSERs, using the methodology described in the next section.…”

Quantum chemistry in environmental pesticide risk assessment

“…The phototoxicity of these emerging pollutants toward Daphnia magna and Scenedemus vacuolatus shows positive correlations between hardness and logEC 50 , while softness only shows a low correlation even negative with D. magna and S. vacuolatus , respectively. Modelling acute‐toxicity of diverse chemicals to D. magna based on electronegativity as a quantum‐chemical descriptor was studied . Philicity [ ω α (r)], which is defined as local electrophilicity, has been proposed as a reliable descriptor for both intermolecular and intramolecular reactivity, including single as well as multiple reactivity centres .…”

“…Modelling acute-toxicity of diverse chemicals to D. magna based on electronegativity as a quantum-chemical descriptor was studied. 22 Philicity [ (r)], which is defined as local electrophilicity, has been proposed as a reliable descriptor for both intermolecular and intramolecular reactivity, including single as well as multiple reactivity centres. 23 The magnitudes of these reactivity descriptors are dependent on the level of theory (e.g.…”