What is meaning of S, P, D, F in Chemistry?

The orbitals are of 4 types. They are named s,p,d,f .The s, p, d, and f stand for sharp, principal, diffuse and fundamental, respectively. The letters and words refer to the visual impression left by the fine structure of the spectral lines which occurs due to the first relativistic corrections, especially the spin-orbital interaction. Technically speaking, an orbital is a wave function for an electron defined by the three quantum numbers, n, ? and ml. What the wave function describes, though, is a region in space with a particular shape, where you are likely to find an electron. In terms of waves, the orbital describes the region in space where the electron density is very thick. In terms of particles, the orbital describes the region in space where there is a high probability of finding the electron (which should make sense, because wherever the electron density is thick, there is also a high probability of finding the electron). read less

The orbitals are of 4 types. They are named s,p,d,f .The s, p, d, and f stand for sharp, principal, diffuse and fundamental, respectively. The letters and words refer to the visual impression left by the fine structure of the spectral lines which occurs due to the first relativistic corrections, especially the spin-orbital interaction. Technically speaking, an orbital is a wave function for an electron defined by the three quantum numbers, n, ? and ml. What the wave function describes, though, is a region in space with a particular shape, where you are likely to find an electron. In terms of waves, the orbital describes the region in space where the electron density is very thick. In terms of particles, the orbital describes the region in space where there is a high probability of finding the electron (which should make sense, because wherever the electron density is thick, there is also a high probability of finding the electron). read less

The orbital shells are giving the names s,p,d,f base on the Spectroscopic transitions involving energy levels with different angular momentun (L) values with different groups of lines in the line spectra of the alkali metals. The line groups were called sharp, principal, diffuse, and fundamental. s- sharp for L=0 p- principal for L=1 d- diffuse for L=2 f- fundamental for L=3 read less