cr has definitions from the field of chemistry
1
[ noun ] (chemistry) a hard brittle blue-white multivalent metallic element; resistant to corrosion and tarnishing

Used in print

(James A. Ibers et al., "Proton magnetic resonance...)

These data lead to a structure in which sheets of Cr atoms lie between two sheets of O atoms .

The O atoms in each sheet are close_packed and each Cr atom is surrounded by a distorted octahedron of O atoms .

Chromium analysis gave 58.8 % Cr as compared with 61.2 % theory .

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