Stereochemically Dependent Synthesis of Two Cu(I) Cluster-Based Coordination Polymers with Thermochromic Luminescence.Two Cu(I) cluster based coordination polymers, [CuI(cis-bpype)]·CH3CN (1) and [Cu4I4(cis-bpype)3(trans-bpype)]·3DMF (2), have been synthesized from cis- and trans-1,2-bis(4-(pyridin-2-yl)phenyl)ethane (cis- and trans-bpype) ligands and {Cu4I4(PPh3)4} as starting materials.  Upon cooling from 300 to 80 K, these Cu(I) cluster based coordination polymers exhibit interesting thermochromic behavior. 
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