photoionization of atom with half-filled shell
1spectroscopy — spectroscopist /spek tros keuh pist/, n. /spek tros keuh pee, spek treuh skoh pee/, n. the science that deals with the use of the spectroscope and with spectrum analysis. [1865 70; SPECTRO + SCOPY] * * * Branch of analysis devoted to identifying… …
2Noble gas — Group 18 Period 1 2 He 2 …
3Caesium — xenon ← caesium → barium Rb ↑ Cs ↓ Fr …
