Estimate of the d–d Overlap of V₂O₅ from ESR Measurements

ESR of TeO2-doped V2O5 single crystals

“…It may be interesting a t this point of the discussion to notice the great similarity between the ESR spectra observed here with those previously reported for Li+doped V205 crystals [12]. It is known that in such Li,V,O, bronzes, lithium is inserted into the channels of the orthorhombic structure.…”

“…The unpaired electron introduced with the lithium remains in the field of this extra positive charge. ESR experiments show that it is delocalized over the four equivalent vanadium sites surrounding the lithium ions in the channel [12]. B 29 hyperfine line spectrum is observed along the b-direction and the ESR parameters are very close to those reported here for Te0,doped V,O,.…”

“…It should rather be due to a slight shift of Te4+ ions from the center towards the edges of the channel. Such a phenomena has already been observed for C o tand Lit-doped V,O, crystals [12]. A calculation of the Couloinb potential J'(r) along the a-direction ( Fig.…”

Optical properties of V<inf>2</inf>O<inf>5</inf> crystals

“…The 1 / signal is connected with V 4+ center (g OE =1.933 and g ŏ =1.974). The EPR signals for V 2 O 5 crystals obtained in other growth conditions with similar parameters were observed in [11,12]. The structure of the 1 / line is not detected since the possible concentration of V 4+ centers is considerable and measuring temperature is high.…”

Electron-spin-resonance study ofNa1−xLixVLohmann1, Nidda2, Loidl3 et al. 2000Phys. Rev. B7010View full textAdd to dashboardCite

“…This clearly indicates that the increase of the linewidth below 34 K is directly connected to the transition, which is suppressed upon lithium doping as will be shown below. In the whole temperature range the ESR signal is strongly exchange narrowed and no hyperfine structure due to the 51 V-spin (I = 7/2) is observed [19]. We therefore propose that the broadening of the linewidth below the transition appears because the exchange narrowing becomes less effective, probably due charge localisation.…”