Crystal chemistry of alpha-quartz is discussed in relation to the nature, concentration and distribution of the common impurities. Two schemes for incorporation of impurities in the host structure, viz. , the charge compensation model for untwinned natural quartz, and the broken-bond model for ...
Alpha-quartz 1. Crystallography and crystal defectsCrystallography of alpha-quartz is discussed with special reference to the existing ambiguities regarding handedness of its enantiomorphic forms and a mnemonic has been suggested. Previous x-ray diffraction topographic studies of synthetic quartz are ...
A theory is presented on the free osculations of a rectangular parallelepiped of piezoelectric crystal, by extending the theory of the rectangular parallel... I Ohno - 《Physics & Chemistry of Minerals》 被引量: 66发表: 1990年 Elastic, anelastic, and piezoelectric coefficients of α -quartz de...
The single-crystal elastic moduli of alpha-quartz were measured to above 20 GPa in a diamond-anvil cell by Brillouin spectroscopy. The behavior of the elastic moduli indicates that the high-pressure phase transition in quartz is ferroelastic in nature and is driven by softening of C44 through ...
Crystal data include lattice parameters and space group information from the International Tables for Crystallography, 4th revised edition 1995, and incorporates the new e-double-glide plane. The type of refinement, along with the final R-values, is listed with the unit cell parameters. Reference ...
The helical crystal structure in alpha-quartz acts as the natural micro-solenoids for an electromagnetic wave passing through them, producing a longitudinal magnetic field in the direction of the optical axis. The longitudinal magnetic field further induces the Larmor frequency for the rotation of the...
The invention relates to a process for obtaining fine-crystalline alpha -quartz having a crystal size of 0.08-0.8 mm. The process comprises carrying out the crystallisation of the amorphous silica in a water vapour atmosphere in the presence of a crystallisation activator - a substance having ...
To better understand the expansion behavior, crystal SiO2 was irradiated by 2 MeV He and 3 MeV Si ions at 44 掳C, 92 掳C and 142 掳C, following step height measurement to quantify the volume change. The amorphization was confirmed by transmission electron microscopy. We found that even ...
The two primary types of device made from quartz crystal plates or wafers, the quartz crystal resonator and the quartz transducer, are described. 关键词: Application, Practical/ crystal resonators piezoelectric transducers quartz/ quartz crystal resonators alpha quartz silica crystallography quartz crystals...
X-band electron paramagnetic resonance experiments on a gamma-irradiated 伪-quartz crystal have revealed a new hydrogarnet-like defect. Analysis of the spe... NS Lees,CJ Walsby,JAS Williams,... - 《Physics & Chemistry of Minerals》 被引量: 30发表: 2003年 加载更多研究...