Miracle ATR ZnSe Top Plate.The ZnSe Top Plate for the Miracle ATR Accessory is ideal for hard samples, acids or alkaline. It has a hardness of 5700 kg/mm, a cutoff cm- spectral range of 525, a refractive index at 1000 cm- of 2.4, a depth of penetration at 45°, of 2.00 and a pH range between 1-14. The Miracle is a universal ATR sampling accessory for analysis of solids, liquids, pastes, gels and intractable materials. In its most popular configuration, it acts as a single reflection ATR accessory with high IR throughput, which makes it ideal for sample identification and QA/QC applications. The easily changeable crystal plate design provides an analysis of a broad spectrum of sample types, while ensuring a constant sampling pathlength.