TY - JOUR
T1 - Novel combination of coordination polyhedra in Mg2Co 3Sn10+x - The first phase in the Mg/Co/Sn system
AU - Schreyer, Martin
AU - Kraus, Günther
AU - Fässler, Thomas F.
PY - 2004
Y1 - 2004
N2 - Mg2Co3Sn10+x is the first compound in the ternary system Mg/Co/Sn. Single crystals for structure analysis were grown from the elements by a tin flux method. The structure (P63/mmc, a = 9.490(1) Å and c = 33.555(7) Å) was determined by X-ray single crystal analysis (R1 = 0.037). A small phase width of 0 ≤ x ≤ 0.15, due to the partial occupancy of one out often tin positions is observed. There are two crystallographically different cobalt sites each with a unique tin coordination sphere. The Col site has a square antiprismatic coordination with tin atoms comparable to the ones observed in the tin rich binary stannides. The Co2 site is characterized by a trigonal prismatic coordination with tin similar to previously known ternary stannides. The different polyhedra are arranged in alternating layers in an intricate way which gives rise to tin-tin distances shorter than 3 A. Magnesium is only found in those layers which have cobalt trigonal prismatically coordinated to tin atoms. Thus, the structure shows an unprecedented arrangement of different coordination spheres, and furthermore provides evidence for homoatomic tin bonding within a metallic framework. Magnetic susceptibility measurements show temperature independent Pauli-paramagnetism down to 50 K.
AB - Mg2Co3Sn10+x is the first compound in the ternary system Mg/Co/Sn. Single crystals for structure analysis were grown from the elements by a tin flux method. The structure (P63/mmc, a = 9.490(1) Å and c = 33.555(7) Å) was determined by X-ray single crystal analysis (R1 = 0.037). A small phase width of 0 ≤ x ≤ 0.15, due to the partial occupancy of one out often tin positions is observed. There are two crystallographically different cobalt sites each with a unique tin coordination sphere. The Col site has a square antiprismatic coordination with tin atoms comparable to the ones observed in the tin rich binary stannides. The Co2 site is characterized by a trigonal prismatic coordination with tin similar to previously known ternary stannides. The different polyhedra are arranged in alternating layers in an intricate way which gives rise to tin-tin distances shorter than 3 A. Magnesium is only found in those layers which have cobalt trigonal prismatically coordinated to tin atoms. Thus, the structure shows an unprecedented arrangement of different coordination spheres, and furthermore provides evidence for homoatomic tin bonding within a metallic framework. Magnetic susceptibility measurements show temperature independent Pauli-paramagnetism down to 50 K.
KW - Intermetallic phases
KW - Metal-metal interactions
KW - Solid-state chemistry
KW - Solid-state structures
UR - http://www.scopus.com/inward/record.url?scp=8844246414&partnerID=8YFLogxK
U2 - 10.1002/zaac.200400296
DO - 10.1002/zaac.200400296
M3 - Article
AN - SCOPUS:8844246414
SN - 0044-2313
VL - 630
SP - 2520
EP - 2526
JO - Zeitschrift fur Anorganische und Allgemeine Chemie
JF - Zeitschrift fur Anorganische und Allgemeine Chemie
IS - 13-14
ER -