Concept

Théorie de l'orbitale moléculaire

Publications associées (215)

Substituent Effect on the Meso-Substituted Porphyrins: Theoretical Screening of Sensitizer Candidates for Dye-Sensitized Solar Cells

Michael Graetzel, Mohammad Khaja Nazeeruddin, Xiaoyu Zhang

According to the concepts of attribute axis and attribute coordinate system, porphine and 11 kinds of bridge carbon substituted porphyrins as donors and 9 common acceptors A-I have been designed and calculated at the density functional B3LYP level. The sub ...

2009

Interplay of electronic correlations and lattice instabilities in BaVS3

Helmuth Berger

The quasi-one-dimensional metallic system BaVS3 with a metal-insulator transition at T-MI=70 K shows large changes in the optical phonon spectrum, a central peak, and an electronic Raman scattering continuum that evolve in a three-step process. Motivated b ...

2009

Density functional theory study of Ir atom deposited on gamma-Al2O3 (001) surface

Iridium adsorption on gamma-Al2O3 (001) surface has been studied using the ab initio calculation method and the electronic structures of the bare and the Ir adsorbed gamma-Al2O3 (001) surfaces have been analyzed. By modeling different adsorption sites, one ...

2009

Multicenter density functionals: revised expression of the standard approximations of exchange-correlation functional

Ursula Röthlisberger, Ivano Tavernelli, I-Chun Lin

We propose to express corrections to the standard approximations of the exchange-correlation functionals in the form of multiatom-centered functionals that can be related to the atoms-in-molecules theory of Bader and a multicenter density expansion. Unlike ...

2009

Retrieving photochemically active structures by time-resolved EXAFS spectroscopy

Majed Chergui, Wojciech Gawelda, Camelia Borca, Van Thai Pham, Amal El Nahhas, Renske Marjan van der Veen, Frederico Alves Lima

Describing the nature and structure of molecular excited states is important in order to understand their chemical reactivity and role as intermediates in photochemical reactions. The recent implementation of x-ray absorption spectroscopy in the ultrafast ...

Iop Publishing Ltd, Dirac House, Temple Back, Bristol Bs1 6Be, England2009

Ultrafast Structural Phase Transition Driven by Photoinduced Melting of Charge and Orbital Order

Paul Beaud

We use femtosecond x-ray diffraction to probe directly the structural dynamics of a charge ordered and orbitally ordered thin film of La0.42Ca0.58MnO3 initiated by an ultrafast optical pulse. At low excitation fluences we observe the displacive excitation ...

American Physical Society2009

Reciprocal requirements for EDA/EDAR/NF-kappaB and Wnt/beta- catenin signaling pathways in hair follicle induction

Yi Zhang

Wnt/beta-catenin and NF-kappaB signaling mechanisms provide central controls in development and disease, but how these pathways intersect is unclear. Using hair follicle induction as a model system, we show that patterning of dermal Wnt/beta-catenin signal ...

2009

Structure and stability of the Si(331)-(12x1) surface reconstruction investigated with first-principles density functional theory

Corsin Battaglia

We recently proposed a structural model for the Si!331"-!12!1" surface reconstruction containing silicon pentamers and adatoms as elementary structural building blocks. Using first-principles density functional theory we here investigate the stability of a ...

2009

Time-dependent density functional theory molecular dynamics simulations of liquid water radiolysis

Ivano Tavernelli

The early stages of the Coulomb explosion of a doubly ionized water molecule immersed in liquid water are investigated with time-dependent density functional theory molecular dynamics (TD-DFT MD) simulations. Our aim is to verify that the double ionization ...

2008

Density-functional theory study of Au, Ag and Cu defects in germanium

Alexandra Sarabando de Carvalho

Gold, silver and copper defects in germanium are modeled using density functional theory. The structures and electrical properties of the substitutional metals are calculated in excellent agreement with experiment. Interstitial Au, Ag and Cu are found to b ...

2008

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