|MadSci Network: Chemistry|
Said compound is the standard for magnetic susceptibility calibration (e.g., Gouy balance). This sounds like a college lab assignment. Visit the college library. You could go to the "Dictionary of Inorganic Compounds" and find the literature references, or Gmelin, Chemical Abstracts; possibly Inorganic Syntheses... I would not be surprised if J. Chemical. Education didn't have some articles on it here and there. The isolated formula unit is obviously a tetrahedrally coordinated cobalt(II) anion and a mercury(II) cation. Looking up the crystal structure is a nice pedagogic exercise for you. Are the thiocyanate ligands bridging, leading to a formally octahedral cobalt(II) in the solid state? BTW, the stuff is immensely toxic. If you measured the magnetic susceptibilty of the stuff, you know the coordination geometry around cobalt by inference, don't you?
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