new type of organic-inorganic hybrid materials based on cadmium iodide (Cdl(2)) and phenethylamine (PEA) has been synthesized and characterized. The reaction of Cdl(2) with PEA in a 1:2 molar ratio yields a four-coordinate hybrid material Cdl(2)(PEA)(2) (1) with extended 1D (Cdl(2))(n) chains, while the reaction of Cdl(2) with PEA in a 1:4 molar ratio produces a six-coordinate hybrid material Cdl(2)(PEA)(4) (2) with a discrete linear structure of Cdl(2) moiety. By introducing a trace amount of Na2S to the reaction for Cdl(2)(PEA)(2), we obtained a new compound [Cdl(2)(PEA)(2)]-(CdS)(0.038) (3) with uniformly doped US nanoparticles. Steady and transient photoluminescence studies reveal that compounds 1 and 2 exhibit bright blue (465 nm) and green (512 nm) fluorescent emissions in solid state at room temperature, respectively, while compound 3 gives a broad and complex emission ranging from 450 to 700 nm. Theoretical studies of electronic structures were carried out using density functional theory in order to gain a good understanding of the luminescent behaviors of these hybrid materials.