Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bond valence calculation for several perovskites and the evidences for a
  valence charge transfer process in these compounds   This paper presents the bond valence calculation for several perovskite
systems and describes the evidences for a valence charge transfer process in
these compounds. The reviewing of the crystal structures of La1-xPbxMnO3
(x=0.1-0.5), La0.6Sr0.4-xTixMnO3 (x=0.0-0.25) and La1-xSrxCoO3 (x=0.1-0.5) is
also presented. On the basis of testing samples, the distribution of valence
charge has been evaluated which showed the failure of elastic bonding mechanism
on all studied systems and revealed the general deficit of valence charge in
the unit cell. This deficit was not equally localized on all coordination
spheres but proved asymmetrically distributed between the spheres. As the
content of substitution increased, the charge deficit declined systematically
from balanced level, signifying the continuous transfer of valence charge from
the B-O6 to A-O12 spheres. The transfered charge varied from system to system,
depending on the valence deviation of spheres and was not small. The total
valence deviation reached near 2electron/unit cell in the studied systems. The
local deviation may be more larger than this average value. The possible impact
of the limitted accuracy of the available structural data on the bond valence
results has been considered.

17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
26
The categories of this paper are: bayes-an
32
The categories of this paper are: atom-ph
25
The categories of this paper are: patt-sol
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio