"The Hamiltonian for the interaction of an atom with a static electric field [called the Stark effect after its discoverer, Johannes Stark (1874-1957); also called the electrochromic effect by other spectroscopists who did not like Stark] is just the electric-dipole interaction:"
Other spectroscopists who did not like Stark?
Why should other spectroscopists not like Stark?
My curiosity was piqued, and it did not take long for me to discover why.
The electrochromic effect it is!