The Lowest Terms in the Spark Spectrum of Nickel and Copper (Ni II and Cu II)

The lowest terms ${}_{}{}^2{}_{}{}^{}D_{2,3}^{}{}_{}{}^{}$ in the spark spectrum of nickel (from the state $d^9$) are found to lie 6884 and 8391 ${\mathrm{cm}}^{-1\mathrm{}}$ below $a^4{F^{\prime }}_5$. In the spark spectrum of copper (Cu II) the lowest term is ${}_{}{}^1{}_{}{}^{}S_0^{}{}_{}{}^{}\left(d^{10}\right)$ and lies 21925 ${\mathrm{cm}}^{-1\mathrm{}}$ below $a^3{D}_3$.