Copper(II) thiocyanate
 Copper(II) thiocyanate
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 Crystal structure of copper(II) thiocyanate
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| Names | |
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| Other names
Cupric thiocyanate
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| Identifiers | |
3D model (
JSmol ) |
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| ChemSpider | |
PubChem CID
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| Properties | |
| Cu(SCN)2 | |
| Molar mass | 179.71 g/mol[1] |
| Appearance | black powder |
| Density | 2.47 g/cm3[1] |
| Melting point | decomposes at 180 C[2] |
| Insoluble | |
| 0.66×10−3 cm3/mol[1] | |
| Related compounds | |
Other anions
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Copper(II) bromide, Copper(II) chloride |
Other cations
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Copper(I) thiocyanate, Cobalt(II) thiocyanate, Mercury(II) thiocyanate, Ammonium thiocyanate Potassium thiocyanate |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Copper(II) thiocyanate (or cupric thiocyanate) is a coordination polymer with formula Cu(SCN)2.[1] It is a black solid which slowly decomposes in moist air.[2] It was first reported in 1838 by Karl Ernst Claus and its structure was determined first in 2018.[3][1]
Structure
The structure of Cu(SCN)2 was determined via powder X-ray diffraction and consists of chains of Cu(NCS)2 linked together by weak Cu–S–Cu bonds into two-dimensional layers. It can be considered a Jahn–Teller distorted analogue of the mercury thiocyanate structure-type. Each copper is octahedrally coordinated by four sulfurs and two nitrogens. The sulfur end of the SCN− ligand is doubly bridging.[1]
Synthesis
Copper(II) thiocyanate can be prepared from the reaction of concentrated solutions of copper(II) and a soluble thiocyanate salt in water, precipitating as a black powder.[2][3] With rapid drying, pure Cu(SCN)2 can be isolated. Reaction at lower concentrations and for longer periods of time generates instead copper(I) thiocyanate.[4]
Magnetism
Copper(II) thiocyanate, like copper(II) bromide and copper(II) chloride, is a quasi low-dimensional antiferromagnet and it orders at 12 K (−261 °C) into a conventional Néel ground state.[1]