"Chemists familiar with conventional quantum mechanics will applaud and benefit greatly from this particularly instructive, thorough and clearly written exposition of density functional theory: its basis, concepts, terms, implementation, and performance in diverse applications. Users of DFT for structure, energy, and molecular property computations, as well as reaction mechanism studies, are guided to the optimum choices of the most effective methods. Well done!" Paul von RaguE Schleyer "A conspicuous hole in the computational chemist's library is nicely filled by this book, which provides a wide-ranging and pragmatic view of the subject.[...It] should justifiably become the favorite text on the subject for practioneers who aim to use DFT to solve chemical problems." J. F. Stanton, J. Am. Chem. Soc. "The authors' aim is to guide the chemist through basic theoretical and related technical aspects of DFT at an easy-to-understand theoretical level. They succeed admirably." P. C. H. Mitchell, Appl. Organomet. Chem. "The authors have done an excellent service to the chemical community. [...] A Chemist's Guide to Density Functional Theory is exactly what the title suggests. It should be an invaluable source of insight and knowledge for many chemists using DFT approaches to solve chemical problems." M. Kaupp, Angew. Chem.

A Chemist's Guide to Density Functional Theory

A scheme that reduces the calculations of ground-state properties of systems of interacting particles exactly to the solution of single-particle Hartree-type equations has obvious advantages. It is not surprising, then, that the density functional formalism, which provides a way of doing this, has received much attention in the past two decades. The quality of the energy surfaces calculated using a simple local-density approximation for exchange and correlation exceeds by far the original expectations. In this work, the authors survey the formalism and some of its applications (in particular to atoms and small molecules) and discuss the reasons for the successes and failures of the local-density approximation and some of its modifications.

The density functional formalism, its applications and prospects

The halogen bond occurs when there is evidence of a net attractive interaction between an electrophilic region associated with a halogen atom in a molecular entity and a nucleophilic region in another, or the same, molecular entity. In this fairly extensive review, after a brief history of the interaction, we will provide the reader with a snapshot of where the research on the halogen bond is now, and, perhaps, where it is going. The specific advantages brought up by a design based on the use of the halogen bond will be demonstrated in quite different fields spanning from material sciences to biomolecular recognition and drug design.

The Halogen Bond

The detection methods and generation mechanisms of the intrinsic reactive oxygen species (ROS), i.e., superoxide anion radical (•O2–), hydrogen peroxide (H2O2), singlet oxygen (1O2), and hydroxyl radical (•OH) in photocatalysis, were surveyed comprehensively. Consequently, the major photocatalyst used in heterogeneous photocatalytic systems was found to be TiO2. However, besides TiO2 some representative photocatalysts were also involved in the discussion. Among the various issues we focused on the detection methods and generation reactions of ROS in the aqueous suspensions of photocatalysts. On the careful account of the experimental results presented so far, we proposed the following apprehension: adsorbed •OH could be regarded as trapped holes, which are involved in a rapid adsorption–desorption equilibrium at the TiO2–solution interface. Because the equilibrium shifts to the adsorption side, trapped holes must be actually the dominant oxidation species whereas •OH in solution would exert the reactivity...

Generation and Detection of Reactive Oxygen Species in Photocatalysis

: 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

Matrix infrared and visible-ultraviolet absorption spectroscopy and ab initio electronic structure calculations have been used to characterize the reaction products from a Tesla coil Ar/CS{sub 2} discharge. The discharge is an excellent source of CS, which reacts with other molecules to form the major C{sub 3}S{sub 2} product and the transient C{sub 2}S{sub 2} species. The spectra of discharged mixed isotopic samples Ar/{sup 12}CS{sub 2}/{sub 13}CS{sub 2} and Ar/C{sup 32}S{sub 2} exhibit triplet patterns in the CS antisymmetric stretching region, which unambiguously identifies the new C{sub 2}S{sub 2} molecule with two equivalent CS subgroups. The magnitudes of the {sup 12,13}C and {sup 32,34}S isotopic shifts further characterize the diatomic CS subgroup nature of C{sub 2}S{sub 2}. Another product contains two equivalent CS subgroups interacting with inequivalent S atom(s). The formation of C{sub 2}S{sub 2}({sup 3}{Sigma}) from the simple CS{sub 2} discharge requires triplet CS. Evidence was also obtained for other transient cumulene species. 32 refs., 8 figs., 7 tabs.

Production and reactions of triplet CS: matrix infrared and ultraviolet spectra of C2S2

Infrared and Raman studies of alkali metal-chlorine reaction products. Resonance Raman spectrum of the chlorine molecular anion, Cl2-

Reactions of the heavy alkali metal atoms with N2O have been studied using the matrix reaction technique. No sodium oxides were produced; however, the metals K, Rb, and Cs yielded products with infrared absorptions appropriate for assignment to ν3 of the M–O–M high‐temperature molecules. The identification of these molecules is based on oxygen isotopic shifts and on experiments codepositing two different alkali metals. Apex angle calculations indicate that K2O and Rb2O have valence angles in the 160°–180° range and that the Cs2O angle is approximately 130°–140°. This trend is rationalized on the basis of increasing metal‐metal bonding with the more polarizable alkali cation. The KO and CsO fundamentals were observed at 384 and 314 cm−1 in solid nitrogen.

Matrix reactions of Na, K, Rb, and Cs atoms with N2O: Infrared spectra and geometries of K2O, Rb2O, and Cs2O

Synthesis of noble-gas dihalides by laser photolysis of matrix-isolated halogens

Laser-ablated rhenium, ruthenium, and osmium atoms react with O2 in excess neon and argon during condensation to form the MO2 dioxide molecules as major products. The MO3 trioxides with D3h symmetr...

Lester Andrews

Papers

Production and reactions of triplet CS: matrix infrared and ultraviolet spectra of C2S2

Infrared and Raman studies of alkali metal-chlorine reaction products. Resonance Raman spectrum of the chlorine molecular anion, Cl2-

Matrix reactions of Na, K, Rb, and Cs atoms with N2O: Infrared spectra and geometries of K2O, Rb2O, and Cs2O

Synthesis of noble-gas dihalides by laser photolysis of matrix-isolated halogens

Infrared Spectra and Density Functional Calculations of MO2, MO3, (O2)MO2, MO4, MO2-(M = Re, Ru, Os) and ReO3-, ReO4-in Solid Neon and Argon†