The chemical bond and the structure of the energy bands in partially covalent tetrahedral crystals

1970 ◽  
Vol 11 (3) ◽  
pp. 473-478 ◽  
Author(s):  
A. A. Levin
Keyword(s):  
1970 ◽  
Vol 10 (6) ◽  
pp. 968-973
Author(s):  
A. A. Levin ◽  
N. M. �nden ◽  
A. A. Dyatkina
Keyword(s):  

Author(s):  
C. A. Coulson ◽  
G. S. Rushbrooke

SummaryThe shapes of the energy bands have been determined for the mobile electrons in graphitic strips of infinite length but finite width, using as a basis the approximation of tight binding discussed for finite crystal layers in the previous paper. It appears that the effect of including overlap between the orbitals of adjacent atoms, whose incorporation in this type of calculation has hitherto been neglected, is to widen the top half of the band by a factor of the order of 2 or 3, the lower half of the band not being greatly affected. Some of these strips may be classed as conductors, the others as insulators; but the distinction between the two may not be made on the basis of any simple chemical bond diagrams.


1962 ◽  
Vol 18 (10) ◽  
pp. 491
Author(s):  
CHEN SHIH-KANG ◽  
CHANG YI-SHANG ◽  
LIOU DE-SEN

1989 ◽  
Vol 86 ◽  
pp. 853-859 ◽  
Author(s):  
Federico Moscardó ◽  
José Pérez-Jordá ◽  
Emilio San-Fabián

2004 ◽  
Vol 9 (4) ◽  
pp. 363-372 ◽  
Author(s):  
T. Lukaszewicz ◽  
A. Ravinski ◽  
I. Makoed

A new multilayer electrochromic device has been constructed according to the following pattern: glass1/ITO/WO3/gel electrolyte/BP/ITO/glass2, where ITO is a transparent conducting film made of indium and tin oxide and with the surface resistance equal 8–10 Ω/cm2 . The electrochromic devices obtained in the research are characterized by great (considerable) transmittance variation between coloration and bleaching state (25–40% at applied voltage of 1.5 to 3 V), and also high coloration efficiency (above 100 cm2 /C). Selfconsistent energy bands, dielectric permittivity and optical parameters are calculated using a full-potential linear muffin-tin orbital method. The numerical solution of the Debye-Smoluchowski equations is developed for simulating recombination probability of Li+ ions in amorphous electrolyte.


Author(s):  
Michael Joshua Landau

Acoustical properties of speech have been shown to be related to mental states such as remission and depression. The objective of this project was to relate the energy in frequency bands with the severity of the mental state using the Beck Depression Inventory (BDI). Recorded speech was obtained from male and female subjects with mental states of remission, depression, and suicidal risk. These subjects had recorded automated and spontaneous speech samples. Multiple regression analysis was used to relate the independent energy band ratio variables with the dependent BDI scores, and thus allow the determination of equitable BDI scores for future patients. For the male group, the square of the 3rd energy band and the cross-product of the 2nd and 3rd energy band were prominent in both the reading and interviewed groups. Therefore the equation with the 2nd lowest Akaike Information Criterion (AIC) score was chosen for the reading male group, and the 1st lowest AIC score was chosen for the interviewed male group. For the female group, the square and cross-product of the 1st and 2nd energy bands were prominent in both the reading and interviewed groups. Therefore the 2nd lowest AIC score was chosen for the reading female group, and the 1st lowest AIC score was chosen for the interviewed female group. The clinician could thus determine the patient’s mood or state of mind by comparing the estimated BDI score with the ranges of total BDI scores: remitted 0 – 20, depressed 15 – 38, suicidal 38 – 46. Keywords: speech, mental states, power spectra, multiple regression, information theoretic criterion


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