Electronic Structure of the Organic Metals κ-Et2cu(SCN)2 and κ-Et2cu[N(Cn)2]Br Measured by Soft X-Ray Emission and Soft X-Ray Absorption

1997 ◽  
Vol 488 ◽  
Author(s):  
Cristian B. Stagarescu ◽  
L.-C. Duda ◽  
Kevin E. Smith ◽  
J. H. Guo ◽  
J. Nordgren ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Density Of States ◽  
Organic Conductors ◽  
Partial Density ◽  
Complex Materials ◽  
Site Specific ◽  
X Ray ◽  
Organic Metals ◽  
X Ray Absorption ◽  
Layered Metals

AbstractThe electronic structure of the two organic, layered metals κ-ET2Cu(SCN)2 and K-ET 2Cu[N(CN)2]Br has been studied using a combination of soft X-ray emission (SXE) and soft X-ray absorption (SXA) spectroscopy. These techniques are powerful probes of the site and angular-momentum resolved partial density of states (PDOS) for both occupied and unoccupied states. Therefore these spectroscopies are particularly suited for an analysis of the density of states of multi-atomic, complex materials as the ET-based organic conductors, allowing site-specific electronic structure to be measured. Furthermore, for certain materials, the electronic structure of specific layers can be measured. We present a preliminary picture of the electronic structure of κ-ET 2Cu(SCN)2 and κ-ET 2Cu[N(CN)2]Br as measured by SXE and SXA performed at the C-Is and N- Is core levels.

Bulk and Surface Electronic Structure of GaN Measured Using Angle-Resolved Photoemission, Soft X-ray Emission and Soft X-ray Absorption

1996 ◽  
Vol 449 ◽  
Author(s):  
Kevin E. Smith ◽  
Sarnjeet S Dhesi ◽  
Laurent-C. Duda ◽  
Cristian B Stagarescu ◽  
J. H. Guo ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Valence Band ◽  
Absorption Spectra ◽  
Conduction Band ◽  
Brillouin Zone ◽  
Emission Spectra ◽  
Partial Density ◽  
High Symmetry ◽  
X Ray ◽  
X Ray Absorption

ABSTRACTThe electronic structure of thin film wurtzite GaN has been studied using a combination of angle resolved photoemission, soft x-ray absorption and soft x-ray emission spectroscopies. We have measured the bulk valence and conduction band partial density of states by recording Ga L- and N K- x-ray emission and absorption spectra. We compare the x-ray spectra to a recent ab initio calculation and find good overall agreement. The x-ray emission spectra reveal that the top of the valence band is dominated by N 2p states, while the x-ray absorption spectra show the bottom of the conduction band as a mixture of Ga 4s and N 2p states, again in good agreement with theory. However, due to strong dipole selection rules we can also identify weak hybridization between Ga 4s- and N 2p-states in the valence band. Furthermore, a component to the N K-emission appears at approximately 19.5 eV below the valence band maximum and can be identified as due to hybridization between N 2p and Ga 3d states. We report preliminary results of a study of the full dispersion of the bulk valence band states along high symmetry directions of the bulk Brillouin zone as measured using angle resolved photoemission. Finally, we tentatively identify a non-dispersive state at the top of the valence band in parts of the Brillouin zone as a surface state.

Electronic structure of twisted and planar rubrene molecules: a density functional study

2018 ◽  
Vol 20 (27) ◽  
pp. 18623-18629 ◽  
Author(s):  
T. Mukherjee ◽  
Sumona Sinha ◽  
M. Mukherjee
Keyword(s):  
Density Functional Theory ◽  
Electronic Structure ◽  
Density Of States ◽  
Electron Density Distribution ◽  
Density Functional ◽  
Functional Study ◽  
Functional Theory ◽  
X Ray ◽  
Homo And Lumo ◽  
X Ray Absorption

X-ray absorption spectra (XAS), the density of states (DOS) and the electron density distribution of the HOMO and LUMO for flat and twisted rubrene molecules have been calculated using density functional theory (DFT).

X-ray Spectroscopic Studies of the Bulk Electronic Structure of InGaN Alloys

2002 ◽  
Vol 743 ◽  
Author(s):  
Cormac McGuinness ◽  
James E. Downes ◽  
Philip Ryan ◽  
Kevin E. Smith ◽  
Dharanipal Doppalapudi ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Band Gap ◽  
Valence Band ◽  
Absorption Spectra ◽  
Conduction Band ◽  
Partial Density ◽  
Significant Shift ◽  
Band Shift ◽  
X Ray ◽  
X Ray Absorption

ABSTRACTSynchrotron radiation excited soft x-ray emission and soft x-ray absorption spectroscopies are applied to the study of the electronic structure of InxGa1-xN alloys with (0 ≤ x ≤ 0.29). The elementally resolved partial density of states of the valence and conduction bands may be measured using these spectroscopies. The x-ray absorption spectra indicate that the conduction band broadens considerably with increasing indium incorporation. The band gap evolution as a function of indium content derives primarily from this broadening of the conduction band states. The emission spectra indicate that motion of the valence band makes a smaller contribution to the evolution of the band gap. This gap evolution differs from previous studies on the AlxGa1-xN alloy system, which observed a linear valence band shift through the series (0 < x < 1). Instead in the case of InxGa1-xN the valence band exhibits a significant shift between x = 0 and x = 0.1 with minimal movement thereafter. Furthermore, evidence of In 4d -N 2p and Ga 3d- N 2p hybridisation is reported. Finally, the thermal stability of an In011Ga089N film was investigated. Both emission and absorption spectra were found to have a temperature dependent shift in energy, but the overall definition of the spectra was unaltered even at annealing temperatures well beyond the growth temperature of the film.

scholarly journals Site specific and doping dependent electronic structure of YBa2Cu3Ox probed by O1s and Cu2p x-ray absorption spectroscopy

1995 ◽  
Vol 71 (1-3) ◽  
pp. 1563-1566 ◽  
Author(s):  
N Nücker ◽  
E Pellegrin ◽  
P Schweiβ ◽  
E Sohmen ◽  
J Fink ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Absorption Spectroscopy ◽  
Site Specific ◽  
X Ray ◽  
X Ray Absorption

Modeling And Photoabsorption Study of YPd2-xRhxB2C Superconductors

2002 ◽  
Vol 731 ◽  
Author(s):  
L.-S. Hsu ◽  
Y. K. Wang ◽  
G. Y. Guo ◽  
Y.-J. Huang ◽  
M.-D. Lan
Keyword(s):  
Fermi Level ◽  
Intermetallic Compounds ◽  
Density Of States ◽  
Electronic Structures ◽  
Theoretical Calculations ◽  
Photoemission Spectrum ◽  
Partial Density ◽  
Superconducting Transition ◽  
X Ray ◽  
X Ray Absorption

AbstractThe electronic structures of six polycrystalline borocarbide superconductors YPd5-xRhxB3C0.4 (x=0, 0.05, 0.1, 0.15, 0.2, and 0.25) were studied by photoemission and photoabsorption spectroscopies and theoretical calculations. The valence-band (VB) photoemission spectrum is compared with the theoretical total and partial density-of-states (DOS) curves. The Pd L3-edge x-ray absorption near edge spectra (XANES) are compared with the calculated XANES spectra for these intermetallic compounds. The decrease of the superconducting transition temperatures (Tc) with addition of Rh dopant in these compounds is due to a decrease of the total DOS at the Fermi level (EF).

Electronic Structure and X-ray Absorption Spectra of Rutile TiO2 Using First-Principles Calculations

2014 ◽  
Vol 52 (12) ◽  
pp. 1025-1029
Author(s):  
Min-Wook Oh ◽  
Tae-Gu Kang ◽  
Byungki Ryu ◽  
Ji Eun Lee ◽  
Sung-Jae Joo ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Absorption Spectra ◽  
First Principles ◽  
First Principles Calculations ◽  
Rutile Tio2 ◽  
X Ray ◽  
X Ray Absorption
Sign in / Sign up

Export Citation Format

Share Document