Three NiAs–Ni2In Type Structures in the Mn–Sn System

A NiAs/Ni2In-Type Phase Ni1+xSn (0.35<x<0.45) with Incommensurate Occupational Ordering of Ni

“…With respect to the occurrence of the commensurate LT and incommensurate LT Ni >V Sn phases in the Ni}Sn system, a similar situation has been reported for the system Mn}Sn (22,23). A commensurate phase Mn Sn isotypic to LT Ni Sn exists.…”

“…A commensurate phase Mn Sn isotypic to LT Ni Sn exists. At higher Mn contents (separated by a rather extended two-phase "eld from Mn Sn ) incommensurate phases were observed (22,23), one being Mn Sn (Mn Sn). The structure of Mn Sn was determined and re"ned using X-ray single crystal di!raction (23) and selected area electron di!raction (22,23).…”

“…At higher Mn contents (separated by a rather extended two-phase "eld from Mn Sn ) incommensurate phases were observed (22,23), one being Mn Sn (Mn Sn). The structure of Mn Sn was determined and re"ned using X-ray single crystal di!raction (23) and selected area electron di!raction (22,23). The super-space group symmetry was, as here for the LT phase, Cmcm( 00)0s0 with an average structure with unit cell parameters a , b , c , and a modulation vector ql " al * with "0.616.…”

Structure of Mn8Sn5

“…As a starting model, the structure was assumed to consist of a basic NiAs-type arrangement, with Sn forming a hexagonally close-packed arrangement and an equimolar amount of Mn (1-3) occupying all octahedral interstices, the remaining Mn (A-C) partially filling the trigonal bipyramidal interstices in an ordered manner (Elding-Pont6n, Stenberg, Larsson, Lidin & Stfihl, 1997).…”

An Electron Diffraction Study of Sn/P and Interstitial Ni Ordering in Ni1+mSn1−xPxB8-type Solid Solutions

“…In addition to Sn/P ordering, there is also the possibility of ordering of the ¹ atoms in the partially filled trigonal bipyramidal sites. It is now well known (4,(7)(8)(9)) that a wide variety of modulated structures (superstructures as well as incommensurately modulated structures) occur within binary ¹ >K B, B8-type phase fields as a result of ordering of filled trigonal bipyramidal sites and associated structural relaxation. On the basis of interatomic separation considerations, Furuseth and Fjellva s g (6) suggested that any Sn/P ordering would be strongly correlated with interstitial Ni ordering and that NiP Sn trigonal bipyramidal clusters should be particularly stable.…”