ChemPhysChem

Cover image for ChemPhysChem

January 13, 2003

Volume 4, Issue 1

Pages 1–110

    1. Cover Picture: ChemPhysChem 1/2003 (page 1)

      Renate Petry, Michael Schmitt and Jürgen Popp

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390000

    2. You have free access to this content
      Editorial: ChemPhysChem in MEDLINE! (pages 3–4)

      Peter Gölitz

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390005

    3. Raman Spectroscopy—A Prospective Tool in the Life Sciences (pages 14–30)

      Renate Petry, Michael Schmitt and Jürgen Popp

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390004

      Thumbnail image of graphical abstract

      Farming with Raman. Raman spectroscopy has undergone a renaissance in recent years and moved away from the straightforward technique encountered early in a chemistry course. These new applications are predominantly in biological systems, where its advantages arising from needing no label, its site specificity, and its insensitivity to water complement other methods favorably. Applications of Raman spectroscopy from cellular processes in plants to microbiological diagnostics are described within.

    4. Accurate Quantum-Chemical Prediction of Enthalpies of Formation of Small Molecules in the Gas Phase (pages 32–48)

      Wim Klopper and Jozef Noga

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390006

      Thumbnail image of graphical abstract

      Elegantly eliminating errors! Can we predict the enthalpies of formation of small molecules in the gas phase accurately to within 1 kJ mol−1 from quantum-chemical calculations? What physical effects and energy corrections must be taken into account to achieve this accuracy? The hierarchical structure of quantum chemistry in terms of basis sets and wavefunctions (see picture) is discussed and calculations on di- and triatomic molecules containing O[BOND]H and O[BOND]F bonds illustrate the quantum-chemical accuracy that is coming within reach.

    5. Molecular Logic Circuits (pages 49–59)

      Vincenzo Balzani, Alberto Credi and Margherita Venturi

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390007

      Thumbnail image of graphical abstract

      Although the construction of a “chemical computer” is still far in the future, molecular-level systems can indeed be used to process information in binary format. Molecular devices capable of performing advanced logic operations or reproducing the functions played by complex electronic circuits, as well as mimicking the behavior of neural-type systems, have been investigated. In the example shown, independent input stimuli (light for In1 and a reagent for In2) provoke two distinct fluorescent outputs depending on their presence. Apart from its technological impact, this research is conceptually of the greatest importance in the fields of chemistry, physics, and biology.

    6. On the Dissociation of Aromatic Radical Anions in Solution (pages 61–66)

      Damien Laage, Irène Burghardt, Thomas Sommerfeld and James T. Hynes

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390009

      Thumbnail image of graphical abstract

      A little flexibility goes a long way: Although strict symmetry considerations would forbid the cleavage of halogenated aromatic radical anions into aromatic radicals and halide anions, their fast dissociation is experimentally observed in solution. The critical impact on the ground-electronic-state solution reaction of a conical intersection (shown in picture)—which describes how the molecule bends a little to circumvent the forbidden dissociation pathway—is studied within a new theoretical formulation.

    7. Correlation of Molecular Assembly and Interactions in Crystals and Langmuir–Blodgett Films of N-(2,4-dinitrophenyl)-n-octadecylamine (pages 67–71)

      Sonika Sharma and T. P. Radhakrishnan

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390010

      Thumbnail image of graphical abstract

      Interactive films: Crystal structure analysis of an amphiphilic molecule, electronic absorption spectra of its solid, solution, and Langmuir–Blodgett film, and quantum-chemical computations on its supramolecular assemblies are used to model the molecular interactions in the Langmuir–Blodgett films and delineate the correlation between 2D and 3D molecular organizations (see picture).

    8. Gas-Phase Chemistry of Ethynylamine, -Phosphine and -Arsine. Structure and Stability of their Cu+ and Ni+ Complexes (pages 72–78)

      Luis Galiano, Manuel Alcamí, Otilia Mó and Manuel Yáñez

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390011

      Thumbnail image of graphical abstract

      Seventeen structures featuring three elements of group five. Significant differences between nitrogen-containing and phosphorus- or arsenic-containing compounds have been found regarding structural effects upon metal cation association (two such structures are shown). The calculated Cu+ and Ni+ binding energies for attachment to the heteroatom follow a different trend to that predicted for the corresponding proton affinities.

    9. Monte Carlo Simulation of the Assembly of bis-Biotinylated DNA and Streptavidin (pages 79–83)

      Jan Richter, Michael Adler and Christof M. Niemeyer

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390012

      Thumbnail image of graphical abstract

      How the net works. Monte Carlo simulations of the experimentally observed self-assembly of biotinylated DNA with the tetravalent biotin-binding protein streptavidin (see graphic) were used to study the STV binding probabilities for the four possible valencies. The results suggest that the binding probability for divalent STV formation is about 50-fold larger than for the formation of trivalent STV and about 200-fold larger than for tetravalent.

    10. Organisation and Reactivity of Nanoparticles at Molecular Interfaces. Part II. Dye Sensitisation of TiO2 Nanoparticles Assembled at the Water|1,2-Dichloroethane Interface (pages 85–89)

      David J. Fermín, Henrik Jensen, Jacques E. Moser and Hubert H. Girault

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390013

      Thumbnail image of graphical abstract

      Contactless dye-sensitised nano-photoelectrodes assembled at polarisable liquid|liquid interfaces exhibit photocurrent responses originating from the heterogeneous photooxidation of ferrocene by the colloids. The photocurrent spectra of the nanoparticle assembly sensitised by alizarin indicate that the photoreaction is initiated by an ultrafast electron injection from the dye into the conduction band of the TiO2 particles, followed by heterogeneous electron transfer from ferrocene to the oxidised dye, as shown.

    11. Transient Optical Studies of Interfacial Energetic Disorder at Nanostructured Dye-Sensitised Inorganic/Organic Semiconductor Heterojunctions (pages 89–93)

      Saif A. Haque, Taiho Park, Andrew B. Holmes and James R. Durrant

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390014

      Thumbnail image of graphical abstract

      Broadening needs energy: Hole-transfer reactions at a dye-sensitised nanocrystalline TiO2/organic hole-conductor (HTM) interface are mainly driven by the free energy difference ΔG(dye-HTM). Inhomogeneous broadening of ΔG(dye-HTM) controls the yield of this interfacial charge-transfer reaction (see picture, curve b) and is therefore an important limitation on the voltage output of photovoltaic devices based upon such interfaces.

    12. Reactivity of the Convex and Concave Surfaces of Single-Walled Carbon Nanotubes (SWCNTs) towards Addition Reactions: Dependence on the Carbon-Atom Pyramidalization (pages 93–97)

      Zhongfang Chen, Walter Thiel and Andreas Hirsch

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390015

      Thumbnail image of graphical abstract

      Angle is more important than diameter: (n,n) Single-walled carbon nanotubes (SWCNTs; see picture) are less reactive than fullerene towards exohedral addition reactions. The reactivity of (n,n) SWCNTs towards sidewall addition reactions depends on the pyramidalization angles of the tube C atoms. Even with the same diameter, SWCNT has a much smaller pyramidalization angle because of the cyclic bending (instead of spherical as in fullerene). The difference between inside and outside reactivity of SWCNTs is only moderate for typical examples such as (10,10) SWCNTs, and the accompanying endohedral adduct formation seems possible.

    13. Rydberg–Valence Interactions in Monoolefins: Dispersing Electronic Properties in 1,1′-Bicyclohexylidene (pages 97–101)

      Rolf A. Rijkenberg, Wybren J. Buma, Joop H. van Lenthe, Leonardus W. Jenneskens and Leonard P. Schmal

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390016

      Thumbnail image of graphical abstract

      Disentangling the embrace: Calculations on the electronic structure of 1,1′-bicyclohexylidene (shown in the graphic) indicate that electronic coupling of the excited ππ* valence state with Rydberg states lies at the basis of the hitherto poorly understood presence of two low-lying electronic states with valencelike properties. States with similar characteristics are predicted for the entire class of monoolefins.

    14. A Photochromic Liquid Crystal System (pages 101–103)

      Michel Frigoli and Georg H. Mehl

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390001

      Thumbnail image of graphical abstract

      Deep Purple, a new photoactive group: The combination of a heteroaromatic diarylethene core (shown in the graphic) separated from mesogenic cyanobiphenyl groups by alkyl spacers allows the synthesis of photochromic liquid crystalline systems with nematic and smectic C phase behaviour between room temperature and 80 °C.

    15. Preview: ChemPhysChem 1/2003 (page 110)

      Version of Record online: 30 DEC 2002 | DOI: 10.1002/cphc.200390003

SEARCH

SEARCH BY CITATION