Lanthanide–TCNQ Magnet A Rare-Earth Metal TCNQ Magnet: Synthesis, Structure, and Magnetic Properties of {[Gd 2 (TCNQ) 5 (H 2 O) 9 ][Gd(TCNQ) 4 - (H 2 O) 3 ]}·4H 2 O** Hanhua Zhao, Mervin J. Bazile, Jr., JosØ R. Galµn- Mascarós, and Kim R. Dunbar* One of the most rapidly expanding areas of coordination chemistry research is the design of magnetic materials based on molecular building blocks. [1] A perusal of the literature reveals that a successful design strategy for preparing molecular magnets is the coordination of organic radicals such as nitronyl nitroxides [2] and organocyanides such as TCNE  C (tetracyanoethylene) [3] and TCNQ  C (7,7,8,8-tetra- cyanoquinodimethane) [4] to paramagnetic transition metal ions.Thepresenceofbothmetalspins(typically S > 1/2)and organic spin carriers (S = 1/2) leads to strong local super- [*] Prof. K. R. Dunbar, H. Zhao, M. J. Bazile, Jr. Department of Chemistry Texas A&M University College Station, TX 77842–3012 (USA) Fax: (+ 1)979-845-7177 E-mail: dunbar@mail.chem.tamu.edu Dr. J. R. Galµn-Mascarós Instituto de Ciencia Molecular Universidad de Valencia Dr. Moliner, 50, 46100 Burjasot (Spain) [**] K.R.D. gratefully acknowledges the National Science Foundation for a Nanoscale Science and Engineering NIRT Grant (DMR-0103455) and a PI Grant (CHE-9906583) and for equipment grants to purchase the CCD X-ray equipment (CHE-9807975) and the SQUID magnetometer (NSF-9974899). H.Z. acknowledges the Science and Technology Committee of Jiangsu Province of China for the donation of f-block starting materials. M.J.B. thanks the Welch Foundation (A1449) and NSF (CHE-9906583) for support and Professor T. R. Hughbanks for his helpful advice and discussion. TCNQ = 7,7,8,8-tetracyanoquinodimethane. Supporting information for this article is available on the WWW under http://www.angewandte.org or from the author. Angewandte Chemie 1015 Angew. Chem. Int. Ed. 2003, 42, No. 9 # 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 1433-7851/03/4209-1015 $ 20.00+.50/0