We have measured the change in the resistive T c of Bi 2 (SrCa) 2ϩn (Cu 1Ϫx M x ) 1ϩn O y whiskers due to substitution of M ϭ Ni ͑magnetic͒ or M ϭ Zn ͑nonmagnetic͒ for Cu. These whisker crystals show resistance drops for both the 2212 and 2223 (nϭ1,2) phases, with transition widths ͑10-90 %͒ of 1 K. We checked the effect of oxygenation at several values of x, and found that T c is maximum for the y obtained by growing and annealing in 1 atm of O 2 . We observed a linear depression of T c for both 2212 and 2223 phases with DϭdT c /dxϷϪ800 K for both Ni and Zn. This is in contrast with YBCO in which D Zn Ϸ3D Ni .

We have used Brillouin scattering to measure the temperature dependence of the sound velocities of the longitudinal and transverse vibrational modes in various directions in small single crystals of monoclinic Zr02. Using these velocities and the Christoffel equation, we have calculated the 13 elastic stiffness moduli between room temperature and the monoclinic-tetragonal transformation temperature.

Saturation magnetizations of V-Fe and Cr-Fe alloys were measured and the results used to determine the average atomic magnetic moment. The linear rate of change of the moment with solute concentration, dp̄B/dC, was found to be −3.286 Bohr magnetons per atom in V-Fe α-phase alloys. Transformation of an approximately equiatomic alloy to the CsCl-ordered α′-phase resulted in a decrease of about 0.4 Bohr magneton in the moment. Subsequent transformation to the σ-phase lowered it by a factor of three. In Cr-Fe solid solution alloys, dp̄B/dC was found to be −2.36 Bohr magnetons per atom.

The elastic stiffness moduli of single-crystals CoAl204, a normal spinel, and CoFe204, an inverse spinel, have been determined by an ultrasonic method. The measured values are: Cll = 290.5, C12 = 170.3 and C44 = 138.6 GPa for CoAl20 4, and Cll = 257.1, C12 = 150.0 and C44 = 85.3 GPa for CoFe204. The elastic constants are compared with previously published data of other spinel single crystals and the results show that the cation valence and cation distribution have little influence on the elastic properties of the spinel materials.

Mi tk» inrraan M In* 0 ■■**• *rwr *• Me immmmcm MM •< «Ma Mkcrs-0m» u* UaUk^.C. IM» w •»»-*»r » *M>* O«i><»i< mi Mkrmr«r< bf aa ■ --J *"" Pr'Osraa k.!0.» AML-fT-721 Publication* File . ■-B. Cblrwik M. V. Mavltt CocTa^nca Proc-dlaga BUtor, on February 22, 1962 at a and Alloy Cbaalatry of Tirana It Ion or the Co-ittaa ot> Alloy Pb*a«« or fjm. to tba ail tor at AXMB CeuTarence *a« praaentad In l«ev York City •ywoalim entitled ''Electronic Structure naaenta" under the auaplcea la to bo eulmitted alloy csbcxbtry or trams mon elskbvts 1-*. H. XL Young 6. ' 7. 8. 9-10-12. 15. A ^O O r r i i M B M 1 ^* DrrRODuc-noK 1. in terw of comgtosi-2. association of structures and 5. the relative stability the past fit: yeurs on occurrence ALLOT CmnCBTRT OF TmWSITIOK EUMDITB bj M. V. Meritt The description and classification of al lay phases tlon and crystal structure. that were not evident earlier and they soae of the earlier uncertainties. new data permit generalbo be recognised concerning the •nd structi-j-e of In **. mediate pfrnrss also provide a cl-r'-ficstloo of phases that Present day studies are of an e^irlcal and perhaps the best Justiat the present tine la the het ttet during a verv considerable amount of crystal c beads try data allty phaser has bear MUai to the literature, iwiejs to be ek> nd trends ®'*:h •» analysis is in an lagwrfect state for the wispiest mti11 1c ■ bruc tures '«nd is almost entirely lacking for the intermediate occur In transition attal systesa. kind, heavily dependent upon experimental data, ficatlon for a critical review structural elements with the ctWLracter and distribution of the bonds between the atoss. An understanding of the factors which determine of the phasis. The realisation of these goals, particularly the last two, will ulti mately need a rigorous quantitative treatment, involvli^ for various strtacture* • detailed knowledge of the distribution of the ho«WHng electrons, spatially and energetically, and the establishment of exact relationships between the energies and configurations of the atoms and electrons and the thermodynamic properties. Alloy chemistry is the title given In the present discussion to the study of the Intermediate phase* in alloy systems, a study which has three closely .-elated goals: MMIMM sub-group". Th. Mrtlcularly ratios and Ftor this reason th. compounds at », families of Isostructural In their tlKuMlon at transition metals and th.tr alloy.. Bkmm-Jtothmry and Oolaa^1^ define th. transition metals aa those which "occupy places in th. Periodic Thbl. at the T1 .sects where groups or 8 electron., which acquire a provisional stability in th. atone of the i*ew yr-----. ex pend into groups of 18 .lactrons by the building up of an (nd)10 Th. lanthanoea are considered to interrupt ths oonal transition xwrcrrnv bartwra La and Bf in the third lone period, and the eLemmta from Ac rainrl are regarded as creaking into the nnrml transition process of the fourth which represent a rather wide variety of .tructure-type.. -5ar* •pectlvely). -typ* at A^B the Cr^O-typ* at A^B th...

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We have measured the constant-pressure heat capacity C, of pure monoclinic ZrOz between 2.75 and 350 K. At low temperatures we find heat capacity in excess of the thermal acoustic phonon contribution, which we attribute to the ingress of low-lying optic mode vibrations. We have calculated the heat capacity at constant volume C, at the hightemperature end of our measurement range and used these values with the harmonic model to derive the moments of the phonon spectrum. Comparing the moments of the monoclinic phase with theoretically derived corresponding moments for the tetragonal phase, we find that a downward shift of optic mode frequencies accompanies the tetragonalto-monoclinic transformation. [

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