  Fluctuations in photon production in scintillator could contribute to the
total energy resolution of a scintillation detector. This contribution, called
intrinsic resolution (IR), is one of the factors limiting the total energy
resolution in detectors based on liquid organic scintillators (LSs). There are
very few experimental measurements of the IR in LSs available, and the
underlying physics is not completely understood. We propose a phenomenological
description of IR of LSs and systematize the data available using a single
universal parameter that characterizes IR. We show that all experimental data
within the model demonstrate the presence of extra smearing of energy
resolution due to IR with a typical value of $\simeq2$\% at 1-MeV energy
release. The model can be used to simulate the effect of IR in LS-based
detectors.
