• journal_title：Mineralogical Magazine
• Contributor：T. Malcherek
• Publisher：Mineralogical Society of Great Britain and Ireland
• Date：2001-
• Format：text/html
• Language：en
• Identifier：10.1180/0026461016560002
• journal_abbrev：Mineralogical Magazine
• issn：0026-461X
• volume：65
• issue：6
• firstpage：709
• section：Articles

Lattice parameters of synthetic titanite powder, CaTiOSiO₄, have been determined between room temperature and 1023 K. Only the e₁₁ and e₁₃ components contribute significantly to the strain tensor associated with the antiferroelectric-paraelectric phase transition at T_c = 487 K. A finite strain component e₁₃ is observed in the paraelectric phase for 487 K < T < 825 K. The disappearance of this shear strain marks the isosymmetric transition near 825 K. The temperature evolution of the volume strain and of e₁₁ is proportional to the squared order parameter observed in single-crystal diffraction experiments. The magnitude of the volume strain is sufficiently large to relate the observed near tricritical behaviour of the antiferroelectric-paraelectric phase transition to strain coupling.