{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T05:34:15Z","timestamp":1788327255728,"version":"build-2803163510"},"reference-count":39,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2016,3,25]],"date-time":"2016-03-25T00:00:00Z","timestamp":1458864000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"United States Department of Energy","award":["DE-SC0008885"],"award-info":[{"award-number":["DE-SC0008885"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>This paper presents results from our exploratory work in the systems K-Cd-Ge, Rb-Cd-Ge, and Cs-Cd-Ge, which yielded the novel type-I clathrates with refined compositions K8Cd3.77(7)Ge42.23, Rb8Cd3.65(7)Ge42.35, and Cs7.80(1)Cd3.65(6)Ge42.35. The three compounds represent rare examples of clathrates of germanium with the alkali metals, where a d10 element substitutes a group 14 element. The three structures, established by single-crystal X-ray diffraction, indicate that the framework-building Ge atoms are randomly substituted by Cd atoms on only one of the three possible crystallographic sites. This and several other details of the crystal chemistry are elaborated.<\/jats:p>","DOI":"10.3390\/ma9040236","type":"journal-article","created":{"date-parts":[[2016,3,29]],"date-time":"2016-03-29T16:00:28Z","timestamp":1459267228000},"page":"236","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Synthesis and Structural Characterization of the New Clathrates K8Cd4Ge42, Rb8Cd4Ge42, and Cs8Cd4Ge42"],"prefix":"10.3390","volume":"9","author":[{"given":"Marion","family":"Sch\u00e4fer","sequence":"first","affiliation":[{"name":"Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3449-3344","authenticated-orcid":false,"given":"Svilen","family":"Bobev","sequence":"additional","affiliation":[{"name":"Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2016,3,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1713","DOI":"10.1126\/science.150.3704.1713","article-title":"Clathrate structure of silicon Na8Si46 and NaxSi136 (x < 11)","volume":"150","author":"Kasper","year":"1965","journal-title":"Science"},{"key":"ref_2","unstructured":"Rowe, D.M. (1995). CRC Handbook of Thermoelectrics, CRC Press."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"978","DOI":"10.1039\/B916400F","article-title":"Thermoelectric clathrates of type-I","volume":"39","author":"Christensen","year":"2010","journal-title":"Dalton Trans."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"178","DOI":"10.1063\/1.121747","article-title":"Semiconducting Ge clathrates: Promising candidates for thermoelectric applications","volume":"73","author":"Nolas","year":"1998","journal-title":"Appl. Phys. Lett."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"528","DOI":"10.1006\/jssc.1999.8354","article-title":"Atomic displacement parameters and the lattice thermal conductivity of clathrate-like thermoelectric compounds","volume":"146","author":"Sales","year":"1999","journal-title":"J. Solid State Chem."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"92","DOI":"10.1006\/jssc.2000.8755","article-title":"Clathrates of group 14 with alkali metals: An exploration","volume":"153","author":"Bobev","year":"2000","journal-title":"J. Solid State Chem."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"842","DOI":"10.1039\/B706808E","article-title":"Inorganic clathrate-II materials of group 14: Synthetic routes and physical properties","volume":"18","author":"Beekman","year":"2008","journal-title":"J. Mater. Chem."},{"key":"ref_8","first-page":"97","article-title":"Zintl clathrates","volume":"Volume 990","author":"Shevelkov","year":"2011","journal-title":"Structure and Bonding"},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Paschen, S., Carrillo Cabrera, W., Bentien, A., Tran, V.H., Baenitz, M., Grin, Y., and Steglich, F. (2001). Structural, transport, magnetic and thermal properties of Eu8Ga16Ge30. Phys. Rev. B, 64.","DOI":"10.1103\/PhysRevB.64.214404"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1096","DOI":"10.1038\/nmat3756","article-title":"Thermopower enhancement by encapsulating cerium in clathrate cages","volume":"12","author":"Prokofiev","year":"2013","journal-title":"Nat. Mater."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1016\/j.physb.2006.03.066","article-title":"New type-I clathrates with ordered Eu distribution","volume":"383","author":"Paschen","year":"2006","journal-title":"Physica. B"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Kishimoto, K., Sasaki, Y., Koyanagi, T., Ohoyama, K., and Akai, K. (2012). Crystal structure and thermoelectric properties of KxBa8\u2013xZnyGe46\u2013y clathrates. J. Appl. Phys., 111.","DOI":"10.1063\/1.4711100"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"4507","DOI":"10.1002\/ejic.200800631","article-title":"A4Ge9 (A = K, Rb) as precursors for Hg-substituted clathrate-I synthesis: Crystal structure of A8Hg3Ge43","volume":"29","author":"Kaltzoglou","year":"2008","journal-title":"Eur. J. Inorg. Chem."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1435","DOI":"10.1002\/zaac.201500147","article-title":"Si-based clathrates with partial substitution by Zn and Ga: K8Zn3.5Si42.5, Rb7.9Zn3.6Si42.4, and Cs8\u2013xGa8\u2013ySi38+y","volume":"641","author":"Baran","year":"2015","journal-title":"Z. Anorg. Allg. Chem."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"3737","DOI":"10.1021\/cm402276n","article-title":"Copper and zinc substitutions in clathrates of tin: Synthesis, structural characterization, and physical properties of A8Cu2.67Sn43.33 and A8Zn4Sn42 (A = K, Rb, Cs) with the type-I structure","volume":"25","author":"Bobev","year":"2013","journal-title":"Chem. Mater."},{"key":"ref_16","first-page":"385404","article-title":"Clathrates Ba8{Zn,Cd}xSi46\u2013x, x~7: Synthesis, crystal structure and thermoelectric properties","volume":"21","author":"Nasir","year":"2009","journal-title":"J. Phys."},{"key":"ref_17","unstructured":"Kauzlarich, S.M. (1996). Chemistry, Structure, and Bonding of Zintl. Phases and Ions, VCH."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"216223","DOI":"10.1088\/0953-8984\/19\/21\/216223","article-title":"Ternary clathrates Ba\u2013Zn\u2013Ge: Phase equilibria, crystal chemistry and physical properties","volume":"19","author":"Grytsiv","year":"2007","journal-title":"J. Phys. Condens. Matter."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"046203","DOI":"10.1088\/0953-8984\/19\/4\/046203","article-title":"Ternary clathrates Ba-Cd-Ge: Phase equilibria, crystal chemistry and physical properties","volume":"19","author":"Grytsiv","year":"2007","journal-title":"J. Phys. Condens. Matter."},{"key":"ref_20","first-page":"319","article-title":"K and Ba distribution in the structures of the clathrate compounds KxBa16\u2212x(Ga,Sn)136 (x = 0.8, 4.4, and 12.9) and KxBa8\u2212x(Ga,Sn)46 (x = 0.3)","volume":"C69","author":"Bobev","year":"2013","journal-title":"Acta. Cryst."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"145","DOI":"10.3390\/cryst1030145","article-title":"Ternary compounds in the Sn-rich section of the Ba-Ga-Sn system: Ba8Ga16\u2013xSn30+x (1.1 \u2264 x \u2264 2.8) clathrates of type-I and type-VIII, and BaGa2\u2013xSn4+x (x \u2248 0.2) with a clathrate-like structure","volume":"1","author":"Yamasaki","year":"2011","journal-title":"Crystals"},{"key":"ref_22","first-page":"679","article-title":"Crystal structure of the clathrate \u03b2-Ba8Ga16Sn30","volume":"213","author":"Peters","year":"1998","journal-title":"Z. Kristallogr. New Cryst. Struct."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"80","DOI":"10.1016\/S0925-8388(99)00531-9","article-title":"Structural disorder and thermal conductivity of the semiconducting clathrate Sr8Ga16Ge30","volume":"296","author":"Chakoumakos","year":"2000","journal-title":"J. Alloys Compd."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1016\/S0925-8388(01)01169-0","article-title":"Structural disorder and magnetism of the semiconducting clathrate Eu8Ga16Ge30","volume":"322","author":"Chakoumakos","year":"2001","journal-title":"J. Alloys Compd."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"3845","DOI":"10.1103\/PhysRevB.61.3845","article-title":"Structural properties and thermal conductivity of crystalline Ge clathrates","volume":"61","author":"Nolas","year":"2000","journal-title":"Phys. Rev. B"},{"key":"ref_26","unstructured":"Pauling, L. (1960). The Nature of the Chemical Bonding, Cornell University Press. [3rd ed.]."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1524\/ncrs.2011.0005","article-title":"Refinement of the crystal structure of K8Ge44\u26102, an intermetallic clathrate I","volume":"226","author":"Llanos","year":"2011","journal-title":"Z. Kristallogr. New Cryst. Struct."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1281","DOI":"10.1002\/zaac.201100187","article-title":"Preparation and crystal structure of the clathrate-I Cs8\u2013xGe44+y\u26102\u2013y","volume":"637","author":"Veremchuk","year":"2011","journal-title":"Z. Anorg. Allg. Chem."},{"key":"ref_29","first-page":"673","article-title":"Crystal structure of the clathrates Rb8In8Ge38 and K8In8Ge38","volume":"213","author":"Menke","year":"1998","journal-title":"Z. Kristallogr. New Cryst. Struct."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1515\/ncrs-1999-0109","article-title":"Crystal structure of the clathrate Cs8In8Ge38","volume":"214","author":"Menke","year":"1999","journal-title":"Z. Kristallogr. New Cryst. Struct."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"79","DOI":"10.3390\/inorganics2010079","article-title":"New type-I and type-II clathrates in the systems Cs\u2013Na\u2013Ga\u2013Si, Rb\u2013Na\u2013Ga\u2013Si, and Rb\u2013Na\u2013Zn\u2013Si","volume":"2","author":"Bobev","year":"2014","journal-title":"Inorganics"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"3795","DOI":"10.1021\/ja9844175","article-title":"Synthesis and characterization of stable stoichiometric clathrates of silicon and germanium: Cs8Na16Si136 and Cs8Na16Ge136","volume":"121","author":"Bobev","year":"1999","journal-title":"J. Am. Chem. Soc."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1076","DOI":"10.1016\/j.jssc.2007.01.003","article-title":"Synthesis and single-crystal X-ray diffraction studies of new framework substituted type II clathrates, Cs8Na16AgxGe136\u2212x (x < 7)","volume":"180","author":"Beekman","year":"2007","journal-title":"J. Solid State Chem."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"365","DOI":"10.1016\/j.jallcom.2008.02.072","article-title":"Synthesis and characterization of framework-substituted Cs8Na16Cu5Ge131","volume":"470","author":"Beekman","year":"2009","journal-title":"J. Alloys Compd."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"3795","DOI":"10.1021\/ja9844175","article-title":"Novel tin clathrates with the type-II structure","volume":"121","author":"Bobev","year":"1999","journal-title":"J. Am. Chem. Soc."},{"key":"ref_36","unstructured":"(2003). SMART NT, version 5.63."},{"key":"ref_37","unstructured":"(2003). SAINT NT, version 6.45."},{"key":"ref_38","unstructured":"(2001). SADABS NT, version 2.10."},{"key":"ref_39","unstructured":"(2001). SHELXTL, version 6.12."}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/9\/4\/236\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T19:21:19Z","timestamp":1760210479000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/9\/4\/236"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2016,3,25]]},"references-count":39,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2016,4]]}},"alternative-id":["ma9040236"],"URL":"https:\/\/doi.org\/10.3390\/ma9040236","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2016,3,25]]}}}