Silver niobium trioxide, AgNbO3

The present structure determination of silver niobium trioxide at 291 K was performed on a twinned single crystal with a predominant presence [about 9 3 (1)%] of one twin domain. The sample contained traces of V (about 1 atomi c %). This study confirms that the room-temperature phase of AgNbO3 is isos tructural with the room-temperature phase of NaNbO3, i.e. it is a tilted pe rovskite. Structural deviation in AgNbO3 from centrosymmetry was not detect ed in this study and its structure was refined in Pbcm, though a previous s tudy indicated ferroelectricity below 350 K, in contrast with NaNbO3.