"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

Laser-ablated Mo and W atoms react with N2 in excess nitrogen and argon to form the metal nitrides, MN, and ligated complexes, (NN)xMN, the metal dinitrides, NMN, and ligated complexes, (NN)xMN2, and several complexes M(NN)x leading up to the octahedral species with x = 6. On the basis of the resolution of natural abundance Mo isotopes and 15N substitution, the open, bent NMoN molecule valence angle is 106 ± 3°. The dinitride molecules are formed both by direct insertion of metastable metal atoms into dinitrogen and by the addition of atomic nitrogen to the mononitride molecule.

Reactions of Laser-Ablated Mo and W Atoms with Dinitrogen: Infrared Spectra of Metal Nitrides, Dinitrides, and Complexes in Solid Argon and Nitrogen

Fluorescence excitation spectra of the lowest charge transfer state of UF6 isolated in solid argon and krypton at 12 K have been obtained using a pulsed, N2‐laser‐pumped dye laser. The complex, multiline spectrum from 360 to 406 nm is much better resolved than previous absorption spectra and is assigned in terms of the ν1, ν3, ν4, ν5, and ν6 normal modes and their overtones and combinations. The role of Jahn–Teller distortion in the upper state is discussed, and the matrix, neat crystal, and gas spectra are compared. The lifetime of the electric dipole forbidden emission is measured at 600 μs in solid argon.

Laser spectroscopy of matrix‐isolated UF6 at 12 K

Infrared Spectrum of the Au–C60 Complex

FTIR spectra of hydroxylamine-hydrogen fluoride complexes in solid argon

The matrix reactions of alkali bromide salts and HBr and DBr have been investigated in argon matrices. In each case, an intense band was observed from the reaction product, which was assigned to the antisymmetric stretch, ν3, of the HBr2− and DBr2− anions in the M+HBr2− and M+DBr2− ion pairs. Comparisons to literature spectra, in conjunction with quartic deuterium shifts, indicate that the anion has a linear, centrosymmetric geometry in the isolated ion pair. A less intense band was also observed which has been assigned to the combination band ν1+ν3 for the HBr2− anion. Reaction of alkali bromide salts with HCl and alkali chloride salts with HBr have been shown to yield identical absorptions for the M+HClBr− ion pairs. The spectra suggest that both type I and type II HClBr− anions exist, and the resulting form may be determined by cation position.

Lester Andrews

Papers

Reactions of Laser-Ablated Mo and W Atoms with Dinitrogen: Infrared Spectra of Metal Nitrides, Dinitrides, and Complexes in Solid Argon and Nitrogen

Laser spectroscopy of matrix‐isolated UF6 at 12 K

Infrared Spectrum of the Au–C60 Complex

FTIR spectra of hydroxylamine-hydrogen fluoride complexes in solid argon

Infrared spectra of the M+HBr2− and the M+HClBr− ion pairs and their deuterium analogs isolated in argon matrices at 15 K