In order to have an insight into the influence of a foreign aromatic molecule on the assembly1 and photoresponse of coordination entity2, the mixture of Nd2O3 and 2,2-binicotinic acid (H2Bn) was treated in the absence and presence of 4,4-bipyridine (Bpy) and finally gave two new aggregates {[Nd2(Bn)3(H2O)2]·4.5H2O}n (1) and {[Nd2(Bn)3(H2O)2](Bpy)·2H2O}n (2), which were crystallographieally defined of possessing isomorphic coordination motifs that consist of Nd(Ⅲ) and Bn2-and form as undulated sheet, but different lattice species (Fig.1), In crystal packing, the Bpy-free 1 displays a layered stacking of Nd-Bn motifs, like the Bpy-bearing 2, but it gives the assembly details (Fig.2) and supramolecular interactions different from 2.Especially, in 2, there is a strong face-to-face π-π interaction between the pyridine rings of Bpy and Bn2, symbolized by a pycentroid-Pycentroid distance of 3.766 ?.It is for the discrepancy in assembly and supramolecular interactions, 1 and 2 showed different responses to light.