Highly ideal 1D spin chains with S = 1 and S = 3/2

One-dimensional spin chain systems are of great interest due to their exotic quantum phenomena such as quantum spin liquid, fractional excitations and potential for application in spintronic and quantum computing. However, ideal spin chain systems are difficult to realize experimentally, due to small but still finite inter-chain interactions, particularly for chain systems with larger spins such as S = 3/2 and S = 1. Here we have successfully realized highly ideal spin chain candidates based on metal organic frameworks (MOF) containing S = 3/2 Co and S = 1 Ni. These exhibit strong intra-chain interactions of order 250 K, but only very weak inter-chain interactions are expected due to the long organic linker within the MOF. No long range order is found down to 0.5 K based on magnetic susceptibility and heat capacity results. To further confirm whether or not there is long-range magnetic order at very low temperature and examine their respective low temperature excitations to compare with our previous studies of highly ideal S = 1/2 spin chains, we propose ZF and LF muSR measurements down to 50 mK.