Peisach J, Mims W B
Eur J Biochem. 1978 Mar;84(1):207-14. doi: 10.1111/j.1432-1033.1978.tb12158.x.
All mononuclear Cu(II) sites in frozen solution are non-centrosymmetric and, unless physically constrained, will have a tetrahedral distortion away from the usual square planar structure often presented for Cu(II) complexes. Blue copper sites such as are found in azurin and stellacyanin have a greater distortion towards a tetrahedral geometry than do simple Cu(II) complexes. The distortion is comparable to that which is observed for Cu(II)-o-phenanthroline dichloride, a known tetrahedral complex. Blue copper sites possess an axis of asymmetry directed away from g parallel which could arise from a metal-sulfur interaction.
冷冻溶液中的所有单核铜（II）位点都是非中心对称的，并且除非受到物理限制，否则将偏离通常为铜（II）配合物呈现的平面正方形结构而发生四面体畸变。诸如在天青蛋白和星蓝蛋白中发现的蓝铜位点比简单的铜（II）配合物对四面体几何形状的畸变更大。这种畸变与在已知的四面体配合物二氯邻菲罗啉铜（II）中观察到的畸变相当。蓝铜位点具有一条远离g平行方向的不对称轴，这可能源于金属-硫相互作用。
