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

N-Heterocyclic Carbenes in Late Transition Metal Catalysis

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

Since the discovery of organic azides by Peter Griess more than 140 years ago, numerous syntheses of these energy-rich molecules have been developed. In more recent times in particular, completely new perspectives have been developed for their use in peptide chemistry, combinatorial chemistry, and heterocyclic synthesis. Organic azides have assumed an important position at the interface between chemistry, biology, medicine, and materials science. In this Review, the fundamental characteristics of azide chemistry and current developments are presented. The focus will be placed on cycloadditions (Huisgen reaction), aza ylide chemistry, and the synthesis of heterocycles. Further reactions such as the aza-Wittig reaction, the Sundberg rearrangement, the Staudinger ligation, the Boyer and Boyer-Aube rearrangements, the Curtius rearrangement, the Schmidt rearrangement, and the Hemetsberger rearrangement bear witness to the versatility of modern azide chemistry.

Organic Azides: An Exploding Diversity of a Unique Class of Compounds

The review covers the knowledge on photoremovable protecting
groups and includes all relevant chromophores studied in the
time period of 2000–2012; the most relevant earlier works are
also discussed.

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Photoremovable Protecting Groups in Chemistry and Biology: Reaction Mechanisms and Efficacy

Identification par spectrometrie IR des composes d'addition de SiFu avec des bases contenant de l'oxygene formes en matrice d'argon. Analyse des bandes d'absorption. Structure et mode de liaison

Argon matrix investigation of the 1:1 molecular complexes of silicon tetrafluoride with water, methanol, and dimethyl ether

Infrared spectra and structure of the argon-matrix isolated hydrogen difluoride(1-) anion

An ab initio study of the structure, binding energies, electronic distribution, vibrational frequencies, and thermodynamic parameters of possible gas-phase complexes of silicon tetrafluoride with w

Water complexes and hydrolysis of silicon tetrafluoride in the gas phase :an ab initio study

Initial and secondary intermediates in the reactions of OVCl3 and CrCl2O2 with H2O have been characterized by matrix isolation infrared spectroscopy and density functional calculations. Twin jet co-deposition of these reagents led to a series of infrared absorptions that are assigned to the 1:1 molecular complexes between these two species. Irradiation of these matrices with light of λ > 300 nm led to complete destruction of the bands of complexes, and the growth of a number of new bands. These are assigned to the Cl2V(O)OH and ClCr(O)2OH species, as well as to HCl arising from destruction of the complex. Identification of these species was supported by isotopic labeling (18O and 2H), as well as by B3LYP/6-311G+(d,2p) and B3LYP/LANL2DZ density functional calculations. Good agreement was observed between the experimental and computed frequencies. The overall yield of product was low for these system, and was probably a consequence of the low basicity of H2O.

Bruce S. Ault

Papers

Argon matrix investigation of the 1:1 molecular complexes of silicon tetrafluoride with water, methanol, and dimethyl ether

Infrared spectra and structure of the argon-matrix isolated hydrogen difluoride(1-) anion

Water complexes and hydrolysis of silicon tetrafluoride in the gas phase :an ab initio study

Infrared matrix isolation and density functional theory study of intermediates in the reactions of OVCl3 and CrCl2O2 with H2O

Matrix isolation study of the reaction of diborane with hydrogen sulfide: spectroscopic characterization of mercaptoborane, H2BSH