Titanium in the pure state can exist in either of two allotropic forms . 纯钛以两种同素异形的形式存在。
2.
The structures of the principal allotropic forms of all the elements will be discussed in detail as the chemistry of each element is treated . 各种元素的主要的同素异性体的结构，在研究各种元素的化学时再详细地讨论。
