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Thiocyanate [6] is known to be an important part in the biosynthesis of hypothiocyanite by a lactoperoxidase. [7] [8] [9] Thus the complete absence of thiocyanate or reduced thiocyanate [10] in the human body, (e.g., cystic fibrosis) is damaging to the human host defense system.
Two examples are the deep blue [Co(NCS) 4] 2-and the green [Ni(NCS) 4] 2-. [5] Few homoleptic complexes of NCS-feature thiocyanate ligands (S-bonded). Octahedral complexes include [M(SCN) 6] 3-(M = Rh [6] and Ir [7]) and [Pt(SCN) 6] 2-. Square planar complexes include [M(SCN) 4] z-(M = Pd(II), Pt(II), [8] and Au(III)). Colorless [Hg(SCN) 4] 2 ...
HSAB is an acronym for "hard and soft (Lewis) acids and bases".HSAB is widely used in chemistry for explaining the stability of compounds, reaction mechanisms and pathways. It assigns the terms 'hard' or 'soft', and 'acid' or 'base' to chemical species.
The esters of thiocyanic acid have the general structure R−S−C≡N, where R stands for an organyl group. Isothiocyanic acid, HNCS, is a Lewis acid whose free energy, enthalpy and entropy changes for its 1:1 association with a variety of Lewis bases in carbon tetrachloride solution at 25 °C have been reported.
However when counting electrons, negative ions should have extra electrons placed in their Lewis structures; positive ions should have fewer electrons than an uncharged molecule. When the Lewis structure of an ion is written, the entire structure is placed in brackets, and the charge is written as a superscript on the upper right, outside the ...
Thiocyanogen, (SCN) 2, is a pseudohalogen derived from the pseudohalide thiocyanate, [SCN] −, with behavior intermediate between dibromine and diiodine. [2] This hexatomic compound exhibits C 2 point group symmetry and has the connectivity NCS-SCN. [3] In the lungs, lactoperoxidase may oxidize thiocyanate to thiocyanogen [4] or ...
For example, the complex [Ni(dien) 2)] 2+ is more stable than the complex [Ni(en) 3)] 2+; both complexes are octahedral with six nitrogen atoms around the nickel ion, but dien (diethylenetriamine, 1,4,7-triazaheptane) is a tridentate ligand and en is bidentate. The number of chelate rings is one less than the number of donor atoms in the ligand.
Of the 26 "monoisotopic" elements that have only a single stable isotope, all but one have an odd atomic number—the single exception being beryllium. In addition, no odd-numbered element has more than two stable isotopes, while every even-numbered element with stable isotopes, except for helium, beryllium, and carbon, has at least three.