Density functional theory study of the near edge X-ray absorption fine structure and infrared spectroscopy of acetylene and benzene on group IV semiconductor surfaces

Asmuruf, Frans A.; Besley, Nicholas A.

doi:10.1016/j.susc.2008.10.043

Cited by 11 publications

(5 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…More recently, this work was extended to study the adsorption of acetylene and benzene on the related group IV semiconductor surfaces C(100)-2Â1 and Ge(100)-2Â1. 92 The aim of this work was to study the sensitivity of the NEXAFS spectra of the adsorbed molecule to the underlying surface, and inform about the structure of the adsorbed molecules. Table 5 shows the computed excitation energies for excitation from the acetylene C(1s) orbitals to the p*, s Ã XÀC and s Ã CÀH orbitals, where X = C, Si or Ge, for acetylene adsorbed on cluster models of the surfaces.…”

Section: Organic Molecules Adsorbed On Semi-conductor Surfacesmentioning

confidence: 99%

“…We have chosen to extend this work to the related surfaces C(100)-2Â1 and Ge(100)-2Â1. 92 The application of NEXAFS to study these surfaces is less common, however, studies of sulfur atoms adsorbed on Ge(100)-2Â1 and hydrogenated C(100)-2Â1 have been reported. 93,94 The calculations reveal subtle changes in the spectral features between the surfaces that can be understood in terms of the molecular orbitals of the adsorbed acetylene molecule.…”

Section: Organic Molecules Adsorbed On Semi-conductor Surfacesmentioning

confidence: 99%

Section: Organic Molecules Adsorbed On Semi-conductor Surfacesmentioning

confidence: 99%

See 2 more Smart Citations

Time-dependent density functional theory calculations of the spectroscopy of core electrons

Besley

Asmuruf

2010

Phys. Chem. Chem. Phys.

Self Cite

241

380

View full text Add to dashboard Cite

Recent advances in X-ray sources have led to a renaissance in spectroscopic techniques in the X-ray region. These techniques that involve the excitation of core electrons can provide an atom specific probe of electronic structure and provide powerful analytical tools that are used in many fields of research. Theoretical calculations can often play an important role in the analysis and interpretation of experimental spectra. In this perspective, we review recent developments in quantum chemical calculations of X-ray absorption spectra, focusing on the use of time-dependent density functional theory to study core excitations. The practical application of these calculations is illustrated with examples drawn from surface science and bioinorganic chemistry, and the application of these methods to study X-ray emission spectroscopy is explored.

show abstract

Section: Organic Molecules Adsorbed On Semi-conductor Surfacesmentioning

confidence: 99%

Section: Organic Molecules Adsorbed On Semi-conductor Surfacesmentioning

confidence: 99%

Section: Organic Molecules Adsorbed On Semi-conductor Surfacesmentioning

confidence: 99%

See 1 more Smart Citation

Time-dependent density functional theory calculations of the spectroscopy of core electrons

Besley

Asmuruf

2010

Phys. Chem. Chem. Phys.

Self Cite

241

380

View full text Add to dashboard Cite

show abstract

“…Previous theoretical studies of NEXAFS spectra of organic molecules adsorbed on a silicon surface have been performed using small cluster models to describe the surface. − In particular, the silicon clusters employed for the N1s spectra calculations of pyridine adsorbed on Si(100) range from a single dimer Si 9 H 12 to a double dimer Si 21 H 24 cluster . The general idea is that these models should capture the dominant effects.…”

Section: Introductionmentioning

confidence: 99%

N1s and C1s Near-Edge X-ray Absorption Fine Structure Spectra of Model Systems for Pyridine on Si(100): A DFT Simulation

et al. 2014

View full text Add to dashboard Cite

This work presents a density functional theory (DFT) based computational investigation of the NEXAFS spectra of pyridine on the Si(100) surface. The accurate modeling of the adsorbate system is tackled by a preliminary optimization of the surface and of the molecules adsorbed on it performed by a periodic slab methodology. From the optimized periodic structures suitable finite clusters are then cut out and used for the calculation of core excitation energies and oscillator strengths of the adsorbed pyridine. Various adsorption modes are considered and for each of them the polarized spectra at the N-K edge and the C K-edge of the pyridine have been simulated with the transition potential scheme in order to include the core hole relaxation effect. The careful analysis of the calculated polarized features and of the intensity trend with the change of polarization reveals important information on specific details of the adsorbtion geometries and support the comparison with the experiment. The XII, VII, IV on-dimer and cross-trench adsorption modes appear suitable to explain the experimental N1s features observed at low temperature while they cannot account for all the experimental features emerging at room temperature both in the N1s and C1s spectra. To deal with this issue the mode IX geometry is also considered for the presence of an –C=N- (imine) chemical group which appears to play an important role for the interpretation of N1s and C1s spectra at 300K. The long range effects of an extended surface model on the NEXAFS features is also analyzed showing the importance of an accurate modeling of the Si(100) reconstructed surface for a confident simulation of the NEXAFS spectra of the adsorbed pyridine

show abstract

“…Very little loss of accuracy of the excitation energies is observed, while a small degradation in the quantitative accuracy of the oscillator strength has been observed. This method has been successfully applied to molecules in solvent, , on surfaces, − chromophores within protein environments, − within membrane environments and also to the calculation of core excited states, − necessary for understanding near-edge X-ray absorption fine spectra (NEXAFS).…”

Section: Introductionmentioning

confidence: 99%

Accurate Excited State Geometries within Reduced Subspace TDDFT/TDA

Robinson

2014

J. Chem. Theory Comput.

View full text Add to dashboard Cite

A method for the calculation of TDDFT/TDA excited state geometries within a reduced subspace of Kohn-Sham orbitals has been implemented and tested. Accurate geometries are found for all of the fluorophore-like molecules tested, with at most all valence occupied orbitals and half of the virtual orbitals included but for some molecules even fewer orbitals. Efficiency gains of between 15 and 30% are found for essentially the same level of accuracy as a standard TDDFT/TDA excited state geometry optimization calculation.

show abstract

Density functional theory study of the near edge X-ray absorption fine structure and infrared spectroscopy of acetylene and benzene on group IV semiconductor surfaces

Cited by 11 publications

References 55 publications

Time-dependent density functional theory calculations of the spectroscopy of core electrons

Time-dependent density functional theory calculations of the spectroscopy of core electrons

N1s and C1s Near-Edge X-ray Absorption Fine Structure Spectra of Model Systems for Pyridine on Si(100): A DFT Simulation

Accurate Excited State Geometries within Reduced Subspace TDDFT/TDA

Contact Info

Product

Resources

About