الفهرس 
Electronic Conduction in Glasses.Only 14 pages are availabe for public view
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Abstract
I’cund ~_1at :18.~8es \lit.h 8.1’ Fe20J content Less than ?O mole~ were
J’!.’l}vrph(,1H:., ·....hile th059 above 20 mole% were dev i.t.r if’Led ,
It is observed thnt increasing the iron mol ar con tet t in t l,e
amor-phous samp.Ies caused en increase in their d ;c , conductd vit.y , a ;c ,
conductdvt.ty , dielectric constant, and in the freQ”enc:,! of t.he dielectric
As a result of heat treatment, both the d ;c , resistivity and
ac t Iva t Lon energy of the ar or-phous sampLes were found to Lncr-eaae
il’d t.Lal.Iy re a ch in f.: a r exi mun, Pr-o’Longsd heqt t.rea tr-errt give:,) rise to
cor ..;+ant magnf.tude; for bot.h these par-an.et.er-s at va Iue s much lower thFJ.n
H\p T”r.tY.i;r.um. On VIe other hand, devitrified sam Le e ~’1owed no rraxirea in
eitherEor E, hovevsr , on heat treatment both decrease grA.dnal1:r to
cI.c
coincide ”ith the ccr-respondf.n r- amor-phoue values a:’ter ;-teat t~at!”ep.t for
’~O hours. X-ray studies indicate t.ha t cr-vs tn Ll.Lne p”ase~ appear on heat Thbr-moelect.ric pove r meaa-rrer-errts in the t.emper-at ure r-ar gc r~ twee’
400 and SOOoKLndi.ca te t:--6.t all glasses were n-tyne, and ”’’’at t’!.o S~’3bec~ coefficientjfound to be independent of t he sample tempe rature , The
frequency dependen t conductivity showed two regi ons , In the high
temperature region the’activation energies were comparable to those
obtained in doc. measurements. In the l~ temperature region a marked
’”
divergence was observed between the a.c. and d.c. conduction behaviors.
The experimental results support the idea of hopping of electrons
between the iron ions in the different valence states. An atterept to
explain the d.c. and a.c. conductione of this system on the basis of a
band-model and on the basis of structural changes is presented.
Possible applications in terms of the observed properties of this glass
system are suggested.