Abstract
Potassium indium diarsenate(V) was grown under mild hydro-thermal conditions (T = 493 K, 7 d) at a pH value of about 1. It adopts the TlInAs(2)O(7) structure type (P-1, Z = 4) and is closely related to the KAlP(2)O(7) (P2(1)/c) and RbAlAs(2)O(7) (P-1) structure types. The framework topology of KInAs(2)O(7) is built of two symmetrically non-equivalent As(2)O(7) groups which share corners with InO(6) octa-hedra. The K atoms are located in channels extending along [010].