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A D V A N C E D M A T E R I A L S & P R O C E S S E S | J U L Y / A U G U S T 2 0 2 0 9 a laser or electric resistance. They also plan to study the performance of the re- sulting hafnium carbonitride in hyper- sonic conditions, which will be relevant for further application in the aerospace industry. www.en.misis.ru. MAKING MATERIALS WITH METAL CLUSTERS Using wet chemistry, an interna- tional research team synthesized metal cluster material with highly anisotropic electrical conductivity, being a semicon- ductor in one direction and an electrical insulator in other directions. Synthesis of the material and its electrical prop- erties were investigated by Xiamen Uni- versity, China, researchers and the the- oretical characterization of the material was carried out at Jyväskylä University, Finland. The scientists added gold and silver salts and ethynyladamantane molecules in a mixture of methanol and either chloroform or dichloromethane. All of the syntheses produced the same 34-atom silver-gold clusters with an identical atomic structure. But, sur- prisingly, the use of dichloromethane and methanol solvent initiated a polymer- ization reaction after cluster formation in solution and growth of human-hair-thick sin- gle crystals consisting of aligned polymeric chains of the clusters. The crystals be- haved as a semicon- ducting material in the direction of the poly- mer and as an electrical insulator in the cross directions. This behav- ior arises from metal- metal atomic bonding in the polymer di- rection while in the (a) Depiction of linear polymer of the 34-atom silver-gold clusters with the inter-cluster metal-metal bonding in the horizontal di- rection (gold: orange, silver: green, ligand molecules (ethynylad- amantane) are shown by grey sticks). (b) Shows the packing of metal atoms in the cluster polymer. Courtesy of Peng Yuan/ Xiamen University. cross directions the metal clusters are isolated from each other by a layer of the ethynyladamantane. www.jyu.fi/en , www.en.xmu.edu.cn. (a) (b)