Platinum(IV) iodide explained

Platinum(IV) iodide is a inorganic compound with the formula . it is a dark brown diamagnetic solid and is one of several binary iodides of platinum.

Preparation

Platinum(IV) iodide can be prepared from the effect of iodine on platinum:^[1]

Iodide accelerates this process.^[2]

It can also be obtained from the decomposition of hydrogen hexaiodoplatinate(IV) at 80 °C:

Physical properties

Platinum(IV) iodide forms dark brown crystals of several modifications:^[3]

• α-, rhombic crystal system, spatial group P bca,^[4] cell parameters a = 1.290 nm, b = 1.564 nm, c = 0.690 nm, Z = 8;
• β-, cubic crystal system, spatial group P m3m, cell parameters a = 0.56 nm, Z = 1;
• γ-, tetragonal crystal system, spatial group I 41/a, cell parameters a = 0.677 nm, c = 3.110 nm, Z = 8.

Platinum(IV) iodide decomposes in water. It is also soluble in ethanol, acetone, alkali, HI, KI, liquid .^[5]

Chemical properties

It decomposes when heated:

When dissolved in hydroiodic acid, platinum(IV) iodide forms hydrogen hexaiodoplatinate(IV):

Notes and References

1. Book: Wicks . Charles E. . Block . Frank E. . Thermodynamic Properties of 65 Elements: Their Oxides, Halides, Carbides and Nitrides . 1963 . . 92 . 28 March 2024 . en.
2. 10.1016/s0927-0248(00)00033-7 . Dissolution of platinum in methoxy propionitrile containing LiI/I2 . 2000 . Olsen . Espen . Hagen . Georg . Eric Lindquist . Sten . Solar Energy Materials and Solar Cells . 63 . 3 . 267–273 .
3. Book: Macintyre . Jane E. . Dictionary of Inorganic Compounds . 23 July 1992 . . 978-0-412-30120-9 . 3510 . 28 March 2024 . en.
4. Book: Donnay . Joseph Désiré Hubert . Crystal Data: Inorganic compounds 1967-1969 . 1978 . . 153 . 28 March 2024 . en.
5. Web site: Platinum(IV) iodide, 99.95% (Metals basis), Pt 27.3% min., Thermo Scientific Chemicals, Premion Fisher Scientific . . 28 March 2024.