TY - JOUR
T1 - The surface stability of Cr2O3(0 0 0 1)
AU - Cao, Shi
AU - Wu, Ning
AU - Echtenkamp, William
AU - Lauter, Valeria
AU - Ambaye, Haile
AU - Komesu, Takashi
AU - Binek, Christian
AU - Dowben, Peter A.
N1 - Publisher Copyright:
© 2015 IOP Publishing Ltd.
PY - 2015/7/1
Y1 - 2015/7/1
N2 - The surface of chromia (Cr2O3) has a surface electronic structure distinct from the bulk and a packing density distinct from the bulk. More than a demarcation between the solid and the vacuum, the surface differs from the bulk of chromia, not just because of a partial occupancy of chromium sites, but also because of an increased number of unoccupied surface oxygen sites (vacancy sites), evident in angle-resolved core level photoemission. In spite of the structural differences that exist at the surface, there is, as yet, no evidence that these complications affect the surface Debye temperature beyond the most simple of assumptions regarding the lower coordination of the surface. Using low-energy electron diffraction (LEED), the effective surface Debye temperature (∼490 K) is found to be lower than the bulk (∼645 K) Debye temperature of Cr2O3(0 0 0 1). This surface effective Debye temperature, indicative of vibrations along the surface normal, uncorrected for anharmonic effects, has a value reduced from the effective bulk Debye temperature yet close to the value √2 expected from a simple mean field argument.
AB - The surface of chromia (Cr2O3) has a surface electronic structure distinct from the bulk and a packing density distinct from the bulk. More than a demarcation between the solid and the vacuum, the surface differs from the bulk of chromia, not just because of a partial occupancy of chromium sites, but also because of an increased number of unoccupied surface oxygen sites (vacancy sites), evident in angle-resolved core level photoemission. In spite of the structural differences that exist at the surface, there is, as yet, no evidence that these complications affect the surface Debye temperature beyond the most simple of assumptions regarding the lower coordination of the surface. Using low-energy electron diffraction (LEED), the effective surface Debye temperature (∼490 K) is found to be lower than the bulk (∼645 K) Debye temperature of Cr2O3(0 0 0 1). This surface effective Debye temperature, indicative of vibrations along the surface normal, uncorrected for anharmonic effects, has a value reduced from the effective bulk Debye temperature yet close to the value √2 expected from a simple mean field argument.
KW - magneto-electrics
KW - surface Debye temperature
KW - surface stability
KW - surface to bulk core level shift
UR - http://www.scopus.com/inward/record.url?scp=84930959901&partnerID=8YFLogxK
U2 - 10.1088/0953-8984/27/25/255003
DO - 10.1088/0953-8984/27/25/255003
M3 - Article
AN - SCOPUS:84930959901
SN - 0953-8984
VL - 27
JO - Journal of Physics Condensed Matter
JF - Journal of Physics Condensed Matter
IS - 25
M1 - 255003
ER -