Structural transformations in liquid, crystalline, and glassy B2O3 under high pressure
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We present in situ (x-ray diffraction) and ex situ (quenching) structural studies of crystalline, liquid, and glassy B2O3 up to 9 GPa and 1700 K, drawing equilibrium and nonequilibrium phase diagrams of B2O3. Particularly, we have determined the melting curve, the stability regions for crystalline B2O3 I and B2O3 II modifications, the regions of transformations, such as densification or crystallization, for both the liquid and glassy states, including the region of sharp first-order-like transition in liquid B2O3 to a high-density phase near 7 GPa. Quenching experiments also show that the transition to the high-density liquid can occur at much lower pressures in nonstoichiometric melts with an excess of boron. B2O3 is the first glassformer whose transformations in the disordered state have been comparatively studied for both liquid and glassy phases.
PACS numbers64.70.Kb 62.50.+p 61.43.−j 61.50.Ks
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- 1.New Kinds of Phase Transitions: Transformations in Disordered Substances, Ed. by V. V. Brazhkin, S. V. Buldyrev, V. N. Ryzhov, and H. E. Stanley (Kluwer, Dordrecht, 2002), NATO Sci. Ser. II: Math. Phys. Chem., Vol. 81.Google Scholar
- 3.Y. Katayama, Gordon Research Conference on Research at High Pressure, Meriden, NH, USA (2002), private communication.Google Scholar
- 5.F. S. El’kin, V. V. Brazhkin, L. G. Khvostantsev, et al., Pis’ma Zh. Éksp. Teor. Fiz. 75, 413 (2002) [JETP Lett. 75, 342 (2002)].Google Scholar
- 6.J. Krong-Moe, J. Non-Cryst. Solids 1, 269 (1969).Google Scholar
- 9.J. D. Mackenzie and W. F. Claussen, J. Am. Ceram. Soc. 44, 79 (1961).Google Scholar
- 10.F. Dachille and R. Roy, J. Am. Ceram. Soc. 41, 78 (1959).Google Scholar
- 11.D. R. Uhlmann, J. F. Hays, and D. Turnbull, Phys. Chem. Glasses 8, 1 (1967).Google Scholar
- 12.J. Swenson and L. Borjesson, Phys. Rev. B 55, 11138 (1997).Google Scholar
- 13.J. D. Mackenzie, J. Am. Ceram. Soc. 46, 461 (1963).Google Scholar
- 14.A. C. Wright, C. E. Stone, R. N. Sinclair, et al., Phys. Chem. Glasses 41, 296 (2000).Google Scholar
- 19.V. V. Brazhkin and A. G. Lyapin, J. Phys.: Condens. Matter (in press).Google Scholar