Question #7c3a9

1 Answer
Jul 25, 2016

It stands for "sharp" "principal" "diffuse" and "fundamental" - terms coined by some of the early spectroscopists back in the late 19th and early 20th centruries.

Explanation:

Dewar and Liveing coined the terms "sharp" "principal" and "diffuse" to descriube the spectroscopic lines resulting from certain alkali metals. These were later used to denote the orbitals from which the spectral lines originated.

"Fundamental" was coined after the work of Bergmann some years later in 1907.