scholarly journals Role of phonons in negative thermal expansion and high pressure phase transitions in β-eucryptite: Anab-initiolattice dynamics and inelastic neutron scattering study

2017 ◽  
Vol 121 (8) ◽  
pp. 085106 ◽  
Author(s):  
Baltej Singh ◽  
Mayanak Kumar Gupta ◽  
Ranjan Mittal ◽  
Mohamed Zbiri ◽  
Stephane Rols ◽  
...  
Keyword(s):  
High Pressure ◽  
Thermal Expansion ◽  
Phase Transitions ◽  
Inelastic Neutron Scattering ◽  
Negative Thermal Expansion ◽  
Inelastic Neutron ◽  
Scattering Study ◽  
Neutron Scattering Study ◽  
Pressure Phase

Floppy modes and the Boson peak in crystalline and amorphous silicates: an inelastic neutron scattering study

2000 ◽  
Vol 64 (3) ◽  
pp. 435-440 ◽  
Author(s):  
M. J. Harris ◽  
M. T. Dove ◽  
J. M. Parker
Keyword(s):  
Neutron Scattering ◽  
Amorphous Materials ◽  
Inelastic Neutron Scattering ◽  
Inelastic Neutron ◽  
Boson Peak ◽  
Pure Silica ◽  
Transverse Acoustic ◽  
Scattering Study ◽  
Neutron Scattering Study

AbstractWe present the results of an inelastic neutron scattering study of a crystalline polymorph of SiO2 (α-quartz), and a number of silicate glasses (pure silica, SiO2, and three glasses in the alkali series (K,Li)2Si2O5). We demonstrate the presence of the Boson peak in the inelastic spectra of the crystalline and amorphous materials and argue that it arises simply from the dispersion characteristics of transverse acoustic modes. Furthermore, we investigate the role of the lower-energy floppy modes in the inelastic spectra, and show that they are controlled by chemical effects.

Sign in / Sign up

Export Citation Format

Share Document