//! Physical constants and numerical tolerances used throughout the crate.
/// Boltzmann constant (J/K).
pub const BOLTZMANN: f64 = 1.380649e-23;
/// Elementary charge (C).
pub const ELECTRON_CHARGE: f64 = 1.60217662e-19;
/// Convergence tolerance for Newton-Raphson iteration (dimensionless).
pub const NEWTON_TOLERANCE: f64 = 1e-9;