Debye
(dəˈbaɪ)
The name of P. J. W. Debye (1884–1966), Dutch physicist, used attrib. to designate certain phenomena observed and principles enunciated by him, as Debye effect (see quots.); Debye–Hückel theory, a theory concerned with the inter-ionic forces in electrolytes; Debye–Scherrer method, a method for the identification of crystals by photographing the diffraction pattern formed by a beam of X-rays directed on to a powdered sample of the crystal under investigation; Debye temperature, a temperature characteristic of an idealized crystal lattice in Debye's theory of specific heats; also, a temperature calculated for a crystalline solid on the assumption that Debye's theory is a correct description of it; Debye unit, a unit of electrical dipole moment equal to 10-18 e.s.u. (approximately 3·336 × 10-30 coulomb metre).
| 1914 Chem. Abstr. VIII. 2845 A theoretical and mathematical discussion of the Debye effect, i.e., the influence of rizing temp. on Röntgen ray interference phenomena. 1918 Ibid. XII. 2488 A mathematical paper dealing with the Bragg and Debye–Scherrer methods of X-ray spectrometry. 1930 Chem. Soc. Ann. Rep. XXVII. 327 The basis of the Debye–Hückel theory of the properties of electrolytic solutions is the idea of an ionic atmosphere. 1934 Nature 22 Sept. 459/1 The slopes of these lines yield the following moments in Debye units (D = 1 × 10-18 E.S.U.)... The average is 4·25 D. 1944 Jrnl. Chem. Physics XII. 289 A theory in which the Debye characteristic temperature θ was related to the curvature of the interatomic potential energy curve. 1947 Thorpe's Dict. Appl. Chem. (ed. 4) VIII. 228/2 Electric dipole moments are expressed in Debye units (represented d.); 1 d. is equivalent to 10-18 C.G.S. unit. 1955 H. B. G. Casimir in W. Pauli Niels Bohr 119 At temperatures well below the so-called Debye temperature θ only lattice waves with a wave-length of many atomic distances are excited. 1957 Encycl. Brit. XXI. 35/1 When ultrasonic radiation passes through an electrolyte, the ions of one sign are affected differently by rapid changes in density from those of the other sign (Debye effect). |