Along with an ab initio recalculation of the NaHg(X1/2) ground state potential curve we present an identification of the chemiluminescence of the NaHg red bands. Based on quantum simulations of the relevant vibronic transitions following production of the NaHg molecule by the photochemical reaction via the sodium dimer, we propose the nascent population distribution in the upper NaHg(II1/2) state to peak at v′=2, described by a Gaussian distribution with α=0.023.