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Bruce P. Luyendyk Institute for Crustal Studies and Department of Geological Sciences, University of California,
Santa Barbara, California 93106-1100
ABSTRACT
In the process of subducted slab capture, a spreading ridge approaches subparallel to
a subduction zone following the trailing edge of a downgoing plate. Eventually the down-
going plate is too young and small to subduct, and spreading stops. The spreading ridge
stalls many tens of kilometres outboard of the subduction zone. The subducted plate welds
to the outboard plate across the dormant spreading center and is captured by it. The
captured plate then acquires the motion of the plate it welded to. In the southwest Pacific
the Pacific-Phoenix …

W. Y. Ching,
Lizhi Ouyang,
Paul Rulis,
and Hongzhi Yao1
Department of Physics, University of Missouri-Kansas City, Kansas City, Missouri 64110, USA
Department of Physics and Mathematics, Tennessee State University, Nashville, Tennessee 37211, USA
Based on the most recently determined noncubic structure for
-Al2O3 by Menendez-Proupin and Gutierrez,
a comprehensive list of physical properties is investigated theoretically. These include lattice dynamics and
phonon spectra, elastic constants and bulk structural parameters, electronic structure and interatomic bonding,
optical properties, and x-ray absorption near-edge structure
XANES spectra. Compared to similar calcula-
tions of -Al2O3, we find a smaller lowest zone-center vibrational mode at 97.6 cm−1
, a lower heat capacity,
a smaller bulk modulus, and …