Knowledge Bank

The emission spectra of NaMgAl $(C2O4)39H2O$ crystals doped with $Cr+2$ have been obtained at 77 and $4\circ K$. In contrast to the behavior of chromium acetylacetonate, the $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}E\to 4A2$ spectrum is unaffected by increasing the $Cr+2$ concentration from 0.1 to 10 mole percent. Only the lower energy component of $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}E$ is populated at $4\circ K$ and the spectra are not appreciably broadened at $77\circ K$. The $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}E$ splitting is $20cm-1$. Intramolecular vibrations corresponding to the 313, 415, 485, 543, 595, 810, 893, and $1253cm-1$ chromium oxalate modes participate in the emission.