“…When the A cation is divalent, the Y and X anions can be divalent and tetravalent, respectively, as exemplified by Ca 3 OPb, , or trivalent and trivalent, respectively, as exemplified by Ca 3 NSb. , When the A cation is monovalent, the Y and X anions are divalent and monovalent, respectively, as exemplified by Na 3 OCl , and Ag 3 SI. , So far, many antiperovskites have been synthesized, exhibiting a variety of physical properties such as ionic conductivity, − magnetism, − superconductivity, − and negative thermal expansion. , However, for prospective optoelectronic applications, the best-known A 3 OX oxyhalide antiperovskites generally exhibit large bandgaps due to their too strong ionicity . It is expected that replacing each of two octahedral O anions with a combination of two other anions (denoted as Y′ and Y″) to form double antiperovskites A 6 Y′Y″X 2 , where the Y′ and Y″ anions at the octahedral centers are arranged orderly, may enable an effective bandgap engineering for potential optoelectronic applications and further expand the family of antiperovskites. ,− …”