caa a22 4500 467923361 CHVBK 20180406152923.0 cr unu---uuuuu 170328e20060701xx s 000 0 eng 10.1134/S1087659606040110 doi (NATIONALLICENCE)springer-10.1134/S1087659606040110 Thermal expansion of β-BaB2O4 and BaB4O7 borates [Elektronische Daten] [S. Filatov, N. Nikolaeva, R. Bubnova, I. Polyakova] The thermal behavior of β-BaB2O4 and BaB4O7 borates is investigated using high-temperature X-ray powder diffraction analysis. The components of the thermal expansion tensor and the tensor orientation with respect to the crystallographic axes are calculated. Thermal deformations are analyzed in relation to the crystal structure. The thermal expansion of the β-BaB2O4 borate is maximum along the c axis and close to zero in the ab plane. The thermal expansion anisotropy correlates with the layered structure, the orientation of the optical indicatrix, and the thermal ellipsoids of atoms. The thermal expansion of the BaB4O7 borate is studied in three high-temperature X-ray diffraction experiments (two experiments with heating and one experiment with cooling). The thermal expansion of this compound is strongly anisotropic: the expansion is maximum in the ac monoclinic plane, whereas the contraction is observed along the b axis. Pleiades Publishing, Inc., 2006 Filatov S. Crystallography Department, St. Petersburg State University, Universitetskaya nab. 7/9, 199034, St. Petersburg, Russia aut Nikolaeva N. Crystallography Department, St. Petersburg State University, Universitetskaya nab. 7/9, 199034, St. Petersburg, Russia aut Bubnova R. Grebenshchikov Institute of Silicate Chemistry, Russian Academy of Sciences, ul. Odoevskogo 24/2, 199155, St. Petersburg, Russia aut Polyakova I. Grebenshchikov Institute of Silicate Chemistry, Russian Academy of Sciences, ul. Odoevskogo 24/2, 199155, St. Petersburg, Russia aut Glass Physics and Chemistry Nauka/Interperiodica 32/4(2006-07-01), 471-478 1087-6596 32:4<471 2006 32 10720 https://doi.org/10.1134/S1087659606040110 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1134/S1087659606040110 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Filatov S. Crystallography Department, St. Petersburg State University, Universitetskaya nab. 7/9, 199034, St. Petersburg, Russia aut NATIONALLICENCE 700 1- Nikolaeva N. Crystallography Department, St. Petersburg State University, Universitetskaya nab. 7/9, 199034, St. Petersburg, Russia aut NATIONALLICENCE 700 1- Bubnova R. Grebenshchikov Institute of Silicate Chemistry, Russian Academy of Sciences, ul. Odoevskogo 24/2, 199155, St. Petersburg, Russia aut NATIONALLICENCE 700 1- Polyakova I. Grebenshchikov Institute of Silicate Chemistry, Russian Academy of Sciences, ul. Odoevskogo 24/2, 199155, St. Petersburg, Russia aut NATIONALLICENCE 773 0- Glass Physics and Chemistry Nauka/Interperiodica 32/4(2006-07-01), 471-478 1087-6596 32:4<471 2006 32 10720 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer