Non‐Close‐Packed Artificial Opals

Non‐close‐packed artificial opals consisting of face‐centered cubic arrays of spheres interconnected by tubular necks (see Figure and cover) have been obtained. The fabrication method and structural and optical properties are reported. Compared to their close‐packed counterparts, non‐close‐packed opals have: i) much higher porosity and ii) stronger optical scattering, which provokes more intense reflectance peaks caused by larger photonic gaps.