  Liquid scintillator detectors are playing an increasingly important role in
low-energy neutrino experiments. In this article, we describe a generic energy
response model of liquid scintillator detectors that provides energy
estimations of sub-percent accuracy. This model fits a minimal set of
physically-motivated parameters that capture the essential characteristics of
scintillator response and that can naturally account for changes in
scintillator over time, helping to avoid associated biases or systematic
uncertainties. The model employs a one-step calculation and look-up tables,
yielding an immediate estimation of energy and an efficient framework for
quantifying systematic uncertainties and correlations.
