We present two new hybrid meta exchange- correlation functionals, called M06 and M06-2X. The M06 functional is parametrized including both transition metals and nonmetals, whereas the M06-2X functional is a high-nonlocality functional with double the amount of nonlocal exchange (2X), and it is parametrized only for nonmetals.The functionals, along with the previously published M06-L local functional and the M06-HF full-Hartree–Fock functionals, constitute the M06 suite of complementary functionals. We assess these four functionals by comparing their performance to that of 12 other functionals and Hartree–Fock theory for 403 energetic data in 29 diverse databases, including ten databases for thermochemistry, four databases for kinetics, eight databases for noncovalent interactions, three databases for transition metal bonding, one database for metal atom excitation energies, and three databases for molecular excitation energies. We also illustrate the performance of these 17 methods for three databases containing 40 bond lengths and for databases containing 38 vibrational frequencies and 15 vibrational zero point energies. We recommend the M06-2X functional for applications involving main-group thermochemistry, kinetics, noncovalent interactions, and electronic excitation energies to valence and Rydberg states. We recommend the M06 functional for application in organometallic and inorganometallic chemistry and for noncovalent interactions.

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The M06 suite of density functionals for main group thermochemistry, thermochemical kinetics, noncovalent interactions, excited states, and transition elements: two new functionals and systematic testing of four M06-class functionals and 12 other functionals

 Many atmospheric chemicals occur in the gas phase as well as in liquid cloud droplets and aerosol particles Therefore, it is necessary to understand the distribution between the phases According to Henry's law, the equilibrium ratio between the abundances in the gas phase and in the aqueous phase is constant for a dilute solution Henry's law constants of trace gases of potential importance in environmental chemistry have been collected and converted into a uniform format The compilation contains 17 350 values of Henry's law constants for 4632 species, collected from 689 references It is also available at http://wwwhenrys-laworg 

/pdf/compilation-of-henry-s-law-constants-version-4-0-for-water-58il9q0ogv.pdf

Compilation of Henry's law constants (version 4.0) for water as solvent

: 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

Ab initio calculation of vibrational absorption and circular dichroism spectra using density functional force fields

Organic compound emission rates for volatile organic compounds (VOC), gas-phase semivolatile organic compounds, and particle-phase organic compounds are measured from residential fireplace combustion of wood. Firewood from a conifer tree (pine) and from two deciduous trees (oak and eucalyptus) is burned to determine organic compound emissions profiles for each wood type including the distribution of the alkanes, alkenes, aromatics, polycyclic aromatic hydrocarbons (PAH), phenol and substituted phenols, guaiacol and substituted guaiacols, syringol and substituted syringols, carbonyls, alkanoic acids, resin acids, and levoglucosan. Levoglucosan is the major constituent in the fine particulate emissions from all three wood types, contributing 18−30% of the fine particulate organic compound emissions. Guaiacol (2-methoxyphenol), and guaiacols with additional substituents at position 4 on the molecule, and resin acids are emitted in significant quantities from pine wood combustion. Syringol (2,6-dimethoxyphenol) and syringols with additional substituents at position 4 on the molecule are emitted in large amounts from oak and eucalyptus firewood combustion, but these compounds are not detected in the emissions from pine wood combustion. Syringol and most of the substituted syringols are found to be semivolatile compounds that are present in both the gas and particle phases, but two substituted syringols that have not been previously quantified in wood smoke emissions, propionylsyringol and butyrylsyringol, are found exclusively in the particle phase and can be used to help trace hardwood smoke particles in the atmosphere. Benzene, ethene, and acetylene are often used as tracers for motor vehicle exhaust in the urban atmosphere. The contribution of wood smoke to the ambient concentrations of benzene, ethene, and acetylene could lead to an overestimate of the contribution of motor vehicle tailpipe exhaust to atmospheric VOC concentrations.

Measurement of emissions from air pollution sources. 3. C1-C29 organic compounds from fireplace combustion of wood.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/jps.2600840120

Atom/fragment contribution method for estimating octanol-water partition coefficients

QSAR modelling of soil sorption. Improvements and systematics of log KOC vs. log KOW correlations

QSAR models for estimating properties of persistent organic pollutants required in evaluation of their environmental fate and risk.

The reactions of hydroxyl radical with ethene, fluoroethene, and chloroethene have been studied by quantum chemical methods Reactants, prereaction complexes, transition-state structures, and products were optimized and vibrational frequencies were calculated at the UMP2/6-311+G(2d,p) level Transition-state structures are significantly different from the prereaction complexes formed on the reactant side of the MEP The convergence of barrier heights and reaction enthalpies has been systematically investigated with respect to the size and quality of basis set and the treatment of correlation energy The best agreement with experimental results is found at the MP2/aug-cc-pVTZ level of theory Regioselectivity is discussed in terms of two properties of the radical and the investigated alkenes The first factor is the relative spin density in the 3ππ* state of the alkene The second factor is the relative strengths of the product C−O bond, ie, relative stability of the corresponding radical product In the

Reactivity and Regioselectivity of Hydroxyl Radical Addition to Halogenated Ethenes

Ab initio multiconfigurational CASSCF and CASPT2 methods were employed in studying the reaction mechanisms and kinetics of the gas-phase ozone additions to ethene, fluoroethene, and chloroethene up to the formation of the primary addition products (primary ozonides). Reactants, transition-state structures, and products were optimized, and harmonic vibrational frequencies were calculated at the CASSCF/cc-pVTZ level. For kinetic calculations, the electron energies of all the stationary points were further refined by utilizing the CASPT2 method with the optimized CASSCF/cc-pVTZ wave functions taken as the zeroth order. The rate constants and Arrhenius kinetic parameters were finally calculated in terms of the conventional transition-state theory. The favorable conformations of the ozone approach to the two asymmetrically substituted haloalkenes are at first governed by the electrostatic repulsion in the transition-state structures and later by the gradually predominating anomeric effect. The bond formation i...

Theoretical Study of the Mechanism and Kinetics of Gas-Phase Ozone Additions to Ethene, Fluoroethene, and Chloroethene: A Multireference Approach

Models based on chemical structure were developed for the accurate predictions of octanol/water partition coefficients (log K ow ) for chlorinated benzenes and biphenyls (PCBs). The molecular connectivity indices and other topological properties, readily available for all chemicals, were used as molecular descriptors. In the modeling process only K ow data measured by the direct slow-stirring method have been used. Derived models account for 99.9% of the variation in the log K ow data, and partition properties are described best by the 0 χ v index

Aleksandar Sabljić

Papers

QSAR modelling of soil sorption. Improvements and systematics of log KOC vs. log KOW correlations

QSAR models for estimating properties of persistent organic pollutants required in evaluation of their environmental fate and risk.

Reactivity and Regioselectivity of Hydroxyl Radical Addition to Halogenated Ethenes

Theoretical Study of the Mechanism and Kinetics of Gas-Phase Ozone Additions to Ethene, Fluoroethene, and Chloroethene: A Multireference Approach

Modeling octanol/water partition coefficients by molecular topology: chlorinated benzenes and biphenyls