Akahama Y, Kawamura H, Le Bihan T
Faculty Science, Himeji Institute of Technology, 3-2-1 Koto, Kamigohri, Hyogo 678-1297, Japan.
Phys Rev Lett. 2001 Dec 31;87(27 Pt 1):275503. doi: 10.1103/PhysRevLett.87.275503. Epub 2001 Dec 10.
Structural phase transitions of a 3d transition element, titanium, have been investigated at pressures up to 220 GPa at room temperature using a monochromatic synchrotron x-ray diffraction technique. At 140 GPa, the hexagonal (omega) phase was transformed into an orthorhombic (delta) phase with a distorted bcc structure via an intermediate (gamma) phase, which has recently been proposed by Vohra and Spencer [Phys. Rev. Lett. 86, 3068 (2001)]. Both the delta and the gamma phases had a unique zigzag-chain-like structure, which resulted from an orthorhombic distortion. The delta-gamma transition could be explained as a rearrangement of the packing between the zigzag chains.
利用单色同步辐射X射线衍射技术，在室温下对三维过渡元素钛在高达220吉帕的压力下的结构相变进行了研究。在140吉帕时，六方（ω）相通过中间（γ）相转变为具有畸变体心立方结构的正交（δ）相，这一中间相是Vohra和Spencer最近提出的[《物理评论快报》86, 3068 (2001)]。δ相和γ相都具有独特的锯齿链状结构，这是由正交畸变导致的。δ-γ转变可以解释为锯齿链之间堆积的重新排列。
