what is k selection rule?

Answer 1

The k-selection rule, often used in quantum mechanics and atomic physics, states that transitions between energy levels are allowed if they involve changes in the quantum number ( k ) by specific integer amounts, typically related to angular momentum. This rule helps predict which electronic transitions are permitted or forbidden based on the selection of angular momentum states, thereby influencing the spectral lines observed in atomic spectra. The specifics can vary depending on the system and the type of transition (e.g., electric dipole, magnetic dipole).