A+E Networks. On this day in 1969, Americaâs first automatic teller machine (ATM) makes its public debut, dispensing cash to customers at Chemical Bank in Rockville Center, New York.
This modification of the energy levels of a hydrogen atom due to a combination of relativity and spin-orbit coupling is known as fine structure.
Hydrogen. The first chemical element in the periodic table. It has the atomic symbol H, atomic number 1, and atomic weight 1. It exists, under normal conditions, as a colorless, odorless, tasteless, diatomic gas.