The dinuclear copper(I) complexes 1 and 2 were prepared by reacting PNP ligands ArN(PPh₂)₂, (Ar = 2,6-Me₂C₆H₃; L1) with CuCl and CuBr. By altering the position of the methyl substituents from ortho to meta (Ar = 3,5-Me₂C₆H₃; L2), trinuclear copper(I) complexes 3 and 4 were obtained, while the methyl substituent at the para position (Ar = 4-MeC₆H₄; L3) led to the tetranuclear copper(I) complexes 5 and 6. Single crystal X-ray studies show the different Cu···Cu interactions in complexes 1–6 ranging from 2.650 to 2.935 Å. The copper(I) complexes 3–6 were found to exhibit mechanochromic as well as thermochromic luminescent behavior presumably stemming from a decrease in their Cu···Cu distances.