Compounds with niastype structure are seen in the sulphides, selenides, tellurides. The nias structure is a common structure in metallic compounds of. Most group iv elements crystallize with the diamond structure. In alas the nias type structure appears at 14 gpa as a consequence of a transition from the zincblende type structure and the nias phase persists to at least 39 gpa. The idealized nickel arsenide, nias 21, and cadmium iodide, cdi 2 22, types of structure are usually described as consisting of hexagonal closest packings of. Pdf spin crossover, structural change, and metallization. Mnas, mnsb, cras, crsb, vs and tise, having the niastype crystal structure are cal culated for the nonmagnetic state by a selfconsistent. Nonintentionally added substances nias are chemical compounds that are present in food contact materials fcms and could therefore migrate into food, but they are not added for a technical reason during the production process. These structures all have ccpfcc anions and differ only in cation positions. Nias may be described as all the octahedral holes in a hcp of as being filled by ni.
Emergency planning officer hart manager asst medical director risk manager regional pressures co ordination manager call takers admin support assistant emergency planning officers. The idealized nickel arsenide, nias 21, and cadmium iodide, cdi 2 22, types of structure are usually described as consisting of hexagonal closest packings of spheres of as and i, respectively. X ions are in approximately closepacked layers which in turn are stacked in the abab. In nite and tis the nias type structure is stable to at least 69 and 41 gpa, respectively. Nias b8 structure the nias b8 structure is represented by mmxn,where m is a metal ion and x is a b group element. What are the coordination number and geometry of ni.
Stop the rotation and spin the structure so you can see a a view down the hexagonal layers and b a side on view of the layers. What are the coordination number and geometry of as. Structural and electrical properties of nias type compounds under pressure. Compounds adopting the nias structure include nis, nisb, fes and cos.
If you have a user account, you will need to reset your password the next time you login. The crystal structure of nickel arsenide request pdf researchgate. Spin crossover, structural change, and metallization in niastype feo at high pressure. For example, some compounds with the nias structure are. The crystal structure of nickel arsenide request pdf. Mgal2o4 cdcl2 cs2o crcl3 k2o caf2 c diamond srtio3 reo3 cscl fe bcc mg nias zns wu.
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