scholarly journals Electronic Structure of Ferrocene-Substituted Cavitands: A QTAIM and NBO Study

2014 ◽  
Vol 2014 ◽  
pp. 1-5
Author(s):  
Tímea R. Kégl ◽  
László Kollár ◽  
Tamás Kégl
Keyword(s):  
Electronic Structure ◽  
Dft Calculations ◽  
Density Distribution ◽  
Electron Density ◽  
Tilt Angle ◽  
Electron Density Distribution ◽  
Partial Charges ◽  
Methylene Groups

Ferrocene-substituted tetrakis(methyl)resorcin[4]arenes have been investigated by means of DFT calculations employing the gradient-corrected PBEPBE functional. In comparison with ferrocene and simple ansa-ferrocenes containing 2–4 bridging methylene groups, it was found that the tilt angle of the functionalized cyclopentadienyl (Cp) rings strongly influences the electron density distribution of the ferrocenyl moieties. According to NBO analyses, the iron atoms in the cavitands are more positive in comparison to those in ferrocene, whereas they are less positive in ansa-ferrocenes. The partial charges of carbon atoms belonging to Cp rings show some correlation with the tilt angle.

Electron density distribution and electronic structure as tools to study the origin of ferroic states in ferroelectric and magnetic materials

2016 ◽  
Vol 500 (1) ◽  
pp. 26-36
Author(s):  
G. M. Santos ◽  
I. B. Catellani ◽  
R. D. Bini ◽  
G. H. Perin ◽  
L. F. Cótica ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Density Distribution ◽  
Magnetic Materials ◽  
Electron Density ◽  
Electron Density Distribution

A study on α-RuCl3 crystal structure by scanning tunneling microscopy

1989 ◽  
Vol 47 ◽  
pp. 30-31
Author(s):  
H.-J. Cantow ◽  
H. Hillebrecht ◽  
S. Magonov ◽  
H. W. Rotter ◽  
G. Thiele
Keyword(s):  
Crystal Structure ◽  
Density Distribution ◽  
Scanning Tunneling Microscopy ◽  
Electron Density ◽  
Structure Determination ◽  
Electron Density Distribution ◽  
Scanning Tunneling ◽  
Monoclinic Space Group ◽  
Tunneling Microscopy ◽  
X Ray

From X-ray analysis, the conclusions are drawn from averaged molecular informations. Thus, limitations are caused when analyzing systems whose symmetry is reduced due to interatomic interactions. In contrast, scanning tunneling microscopy (STM) directly images atomic scale surface electron density distribution, with a resolution up to fractions of Angstrom units. The crucial point is the correlation between the electron density distribution and the localization of individual atoms, which is reasonable in many cases. Thus, the use of STM images for crystal structure determination may be permitted. We tried to apply RuCl3 - a layered material with semiconductive properties - for such STM studies. From the X-ray analysis it has been assumed that α-form of this compound crystallizes in the monoclinic space group C2/m (AICI3 type). The chlorine atoms form an almost undistorted cubic closed package while Ru occupies 2/3 of the octahedral holes in every second layer building up a plane hexagon net (graphite net). Idealizing the arrangement of the chlorines a hexagonal symmetry would be expected. X-ray structure determination of isotypic compounds e.g. IrBr3 leads only to averaged positions of the metal atoms as there exist extended stacking faults of the metal layers.

Sign in / Sign up

Export Citation Format

Share Document