Iodine as an Oxidant in the Topotactic Deintercalation of Interstitial Iron in Fe_1+<i>x</i>Te

The layered telluride, Fe1+xTe, is a parent compound of the isostructural and superconducting phases, Fe1+x(Te, Se, S). Here we show that, through a simple reaction of I2 vapor with both powder and single crystal samples, the interstitial iron can be removed from the FeTe framework topotactically. Neutron powder diffraction and X-ray single crystal diffraction confirm that the iron being extracted is the partially occupied site that lies between the 2-D blocks of edge-sharing FeTe4 tetrahedra. The deintercalation process has consequences for both magnetic and crystallographic phase transitions in the compound at low temperatures. This technique could be of use for the tuning of stoichiometry of the superconducting phases and therefore enable more careful studies on how chemical composition affects magnetic and superconducting properties.层状碲化物Fe₁₊ₓTe是同构超导相Fe₁₊ₓ(Te, Se, S)的母体化合物。本文证明，通过将I₂蒸气与粉末及单晶样品进行简单反应，可从FeTe骨架中以拓扑方式脱除间隙铁原子。中子粉末衍射与X射线单晶衍射分析证实，被脱除的铁原子对应于共边FeTe₄四面体二维块体之间的部分占据位点。该脱嵌过程会对该化合物低温下的磁学相变与晶体学相变产生影响。此技术可用于调控超导相的化学计量比，进而为更细致地研究化学组成如何影响磁学与超导性能提供可能。