Specular X-ray diffraction and X-ray reflectivity (XRR) measurements were made on a PANalytical EMPYREAN reflectometer using Cu Kα radiation (λ = 1.54 Å). On the primary side, a multilayer X-ray mirror was used to generate a parallel beam. On the secondary side, an anti-scatter slit and 0.02 rad Soller slit were used with a PANalytical PIXcel3D detector. Specular X-ray diffraction and XRR data are plotted as a function of q z, the out-of-plane component of the scattering vector, with q z = 4π/λ sin Θ, where λ is the X-ray wavelength and Θ is half of the scattering angle, 2Θ. XRR data were fitted and the electron density profile of films determined using the Stochfit software package.20