TY - JOUR
T1 - Dielectric response of Fe2O3 crystals and thin films
AU - Lunt, Ruth
AU - Jackson, Adam J.
AU - Walsh, Aron
PY - 2013/10/24
Y1 - 2013/10/24
N2 - We report the static (ε0) and high frequency (ε∞) dielectric constants of haematite (α-Fe2O3) as calculated using density functional perturbation theory. The values for bulk iron oxide are ε0 11 = 26.41; ε0 33 = 17.84; ε∞ 11 = 7.87 and ε∞ 33 = 7.57. The effective static dielectric screening of porous thin-films is predicted in aqueous solutions, using effective medium theory, to range between 33 and 44 depending on the crystal packing density. The large spread in literature values (12-120) can only be explained through surface and micro-structuring effects. These results will be important for interpreting and modelling the materials behaviour, particularly in electrochemical and photoelectrochemical cells.
AB - We report the static (ε0) and high frequency (ε∞) dielectric constants of haematite (α-Fe2O3) as calculated using density functional perturbation theory. The values for bulk iron oxide are ε0 11 = 26.41; ε0 33 = 17.84; ε∞ 11 = 7.87 and ε∞ 33 = 7.57. The effective static dielectric screening of porous thin-films is predicted in aqueous solutions, using effective medium theory, to range between 33 and 44 depending on the crystal packing density. The large spread in literature values (12-120) can only be explained through surface and micro-structuring effects. These results will be important for interpreting and modelling the materials behaviour, particularly in electrochemical and photoelectrochemical cells.
UR - http://www.scopus.com/inward/record.url?scp=84885653414&partnerID=8YFLogxK
UR - http://dx.doi.org/10.1016/j.cplett.2013.09.023
U2 - 10.1016/j.cplett.2013.09.023
DO - 10.1016/j.cplett.2013.09.023
M3 - Article
SN - 0009-2614
VL - 586
SP - 67
EP - 69
JO - Chemical Physics Letters
JF - Chemical Physics Letters
ER -