The UV-vis absorption spectra of (C4H9NH3)2PbX4(X=Br, I) exhibited which respectively at room temperature absorption peak at 405nm and 515nm.

• (C_4H_9NH_3)_2PbX_4(X=Br，I)薄膜室温下UV-vis吸收谱显示它们的吸收峰分别位于405nm和515nm。