Spectroscopic studies of (C10H21NH3)2PbI4, (CH3NH3)(C10H21NH3)2Pb2I7, (CH3NH3) PbI3, and similar compounds

Abstract Compounds (C n H 2n+1 NH 3 ) 2 PbI 4 (n=4,8,10…) are of growing interest as materials for non-linear optical devices. In this paper the room temperature optical absorption and luminescence spectra of (C n H 2n+1 NH 3 ) 2 PbI 4 (n=4,8,10), (CH 3 NH 3 )(C n H 2n+1 NH 3 ) 2 Pb 2 I 7 , (CH 3 NH 3 )PbI 3 and similar compounds (with Br and/or Cl instead of I as well as with Sn instead of Pb) are reported. It was found that the low frequency excitonic (or edge luminescence) bands cover a wide spectral region, namely from ca 330 nm to ca 835 nm. Also, changes in the spectra of these compounds after exposure to several oxidizing reagents are discussed.