| 释义 |
semi-ˈmetal
[ad. mod.L. sēmi-metallum: see semi- 2, 8 i.]
Orig. a non-malleable metal. Now usu. signifying incomplete metallic character in other physical properties, esp. electrical conductivity; spec. an element (as arsenic, antimony, bismuth) or other substance having properties intermediate between those of true metals and those of semiconductors.
1661Lovell Hist. Anim. & Min. Introd. f 2 b, Semi⁓mettals, &c. which are mineral bodies, neere in nature unto mettals. 1671J. Webster Metallogr. 89 [A Metal] may comprehend both those that are strictly called Metals (not excluding common argent vive to be one) and those that are also called semi-metals, as Antimony and the like. 1732Hist. Lit. III. 349 Fossils are divided into Metals, Salts, Sulphurs, Stones, Semi-Metals, and Earths. 1754Lewis in Phil. Trans. XLVIII. 680 Regulus of antimony, the most difficultly fusible of the semi-metals. 1812J. Smyth Pract. Customs 26 Crude Antimony, or the Ore of Antimony,..is a semi-metal. 1831T. P. Jones New Convers. Chem. Gloss., Semi-metal. This term is now obsolete. 1835Poe Adv. Hans Pfaall Wks. 1864 I. 8 A particular metallic substance or semi-metal. 1912W. E. Ford Dana's Man. Mineral. (ed. 13) iv. 115 The semimetals—tellurium, arsenic, antimony and bismuth—belong together in a crystal group, all of them showing rhombohedral crystals with closely agreeing fundamental angles. 1952Chem. Abstr. XLVI. 1187 Semimetals with continuous properties between metals and ceramics. 1972Science 19 May 753/1 There is a clear trend both with increasing pressure and with atomic number from a semiconductor to a semimetal with a distorted simple cubic structure to a metallic, simple cubic phase. |