One parameter that could alter the observed conformer abundances is the deposition angle. To test for such angular dependence, dilute samples of 500:1 CH3ONO in different bath gases were condensed onto a cold substrate at different deposition angles, ranging from α = 20° and α = -10° in increments of 10°. Due to the symmetry of the experimental setup, negative deposition angles should yield the same results as their corresponding positive angles, though small deviations in results may occur due to changes in the orientation of the heat shield relative to the beam (see Section 2.1 for more details). Conformer abundances in the matrix were measured using matrixisolation spectroscopy (see SM Section 5, Figure ) and compared as before to the gas-phase abundance.