"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

Vibronic absorption spectra of condensed ring aromatic cation systems in solid argon

Pulsed laser evaporated boron atoms codeposited with Ar/CO 2 samples give a strong product band at 18634 cm -1 that shows boron, carbon, and oxygen isotopic shifts Ab initio calculations predict two strong infrared bands for the BOCO addition product and one strong band, which scales to the observed band position, for the OBCO insertion product The calculated and observed frequencies exhibit isotopic shifts appropriate for an «antisymmetric» O-B, C-O stretching fundamental in a bent OBCO molecule

Reaction of boron atoms with carbon dioxide: matrix and ab initio calculated infrared spectra of OBCO

The vibration–rotational and pure rotational laser–Raman spectra of H2, D2, and HD were observed in argon, krypton, xenon, nitrogen, and oxygen matrices at 12 K. Transitions arising from the J=0 and J=1 rotational levels were seen for H2 and D2, but from only the J=0 level for HD. Only transitions from the J=0 level were observed for H2 in an oxygen matrix. It is interesting that hydrogen is trapped at all in an inert gas matrix at 12 K; this indicates that hydrogen molecule–inert gas atom interactions are stronger than hydrogen–hydrogen interactions.

Vibration–rotational and pure rotational laser–Raman spectra of H2, D2, and HD in matrices at 12 K

Laser-ablated thorium atoms react with ammonia to form thorimine (NH=ThH 2 ), the first actinide imine to be reported. This work underscores the high reactivity of thorium atoms, particularly for N-H bond activation, reveals a new type of multiple bond to actinide atoms, and shows that this bond is strong for thorium as a result of an important contribution from the f orbitals.

Infrared Spectrum and Structure of Thorimine (HNThH2)

Infrared spectra of representative LnH1-4 lanthanide hydride molecules are observed in solid argon following reactions of the laser-ablated metal atoms with H2. The LnH2 dihydride is the major product and a stable (H2)LnH2 complex is observed for Ce and Pr. In addition, bands are also assigned to bridging hydrogen motions of several (LnH)2 dimers. Supplementary density functional calculations of the lanthanide hydride reaction products reproduce general features of the spectra. Spectra of isolated molecular EuH2 and solid stoichiometric EuH2 reveal close correspondence, lending support to the molecular assignment and, by extrapolation, providing benchmark infrared frequencies for other lanthanide hydride solids based on their respective molecular vibrational modes.

Characterization of the Reaction Products of Laser-Ablated Lanthanide Metal Atoms with Molecular Hydrogen. Infrared Spectra of LnH, LnH2, LnH3, and LnH4 Molecules in Solid Argon

Lester Andrews

Papers

Vibronic absorption spectra of condensed ring aromatic cation systems in solid argon

Reaction of boron atoms with carbon dioxide: matrix and ab initio calculated infrared spectra of OBCO

Vibration–rotational and pure rotational laser–Raman spectra of H2, D2, and HD in matrices at 12 K

Infrared Spectrum and Structure of Thorimine (HNThH2)

Characterization of the Reaction Products of Laser-Ablated Lanthanide Metal Atoms with Molecular Hydrogen. Infrared Spectra of LnH, LnH2, LnH3, and LnH4 Molecules in Solid Argon