High-density electron anions in a nanoporous single crystal: [Ca24Al28O64]4+(4e-).
We removed approximately 100% of clathrated oxygen ions from the crystallographic cages in a single crystal of 12CaO.7Al2O3, leading to the formation of high-density (approximately 2 x 10(21) cm-3) electrons highly localized in the cages. The resulting electron forms a structure that we interpret as an F+ center and migrates throughout the crystal by hopping to a neighboring cage with conductivity approximately 100 siemens per centimeter, demonstrating that the encaged electron behaves as an anion. The electron anions couple antiferromagnetically with each other, forming a diamagnetic pair or singlet bipolaron. The resulting [Ca24Al28O64]4+(4e-) may be regarded as a thermally and chemically stable single crystalline "electride."
Matsuishi
Satoru
S
Hosono Transparent and Electro-Active Materials Project, Exploratory Research for Advanced Technology (ERATO), Japan Science and Technology Corporation, KSP C-1232, 3-2-1 Sakado, Takatsu-ku, Kawasaki 213-0012, Japan.
Toda
Yoshitake
Y
Miyakawa
Masashi
M
Hayashi
Katsuro
K
Kamiya
Toshio
T
Hirano
Masahiro
M
Tanaka
Isao
I
Hosono
Hideo
H