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1Author    Falk Lissner, FrankA. Weber, Thomas SchleidRequires cookie*
 Title    Drei Formen des Samarium(III)-Sulfidselenids Sm2S2_JC Se1+A . (0,1 < x < 0,2) Three Types of the Samarium(III) Sulfide Selenide Sm2S2_ vSe1+JC (0.1 < x < 0.2)  
 Abstract    Single crystals of Sm2 S2 -jSe1+x (0.1 < x < 0.2) have been obtained for the first time through the oxidation of KSm2Cl5 with an excess of sulfur and selenium in equimolar amounts at 850 °C after seven days in evacuated silica tubes. They emerged as almost black, in thin layers deep red, lath-shaped needles (A and U type, respectively) as well as red, bead-shaped polyhedra (C type) of the gross chemical composition Sm2S2Se according to X-ray structure analyses. A much simpler method of synthesis is based on the direct fusion of the elements (samarium, sulfur and selenium) in appropriate molar ratios (2:2:1) in the presence of NaCl as a flux under otherwise analogous conditions (silica tubes, 7 d, 850 °C). A-Sm2 S1.82Se1.18 crystallizes orthorhombically (a = 753.1(3), b = 401.9(1), c = 1565.8(6) pm, Z = 4) in the space group Pnma with the a-G d2 S3-type structure. Two crystallographically different Sm3+ cations are coordinated by eight (Sm l) and seven (Sm2) Ch2~ anions (S2_ and Se2 -) as bi-and monocapped trigonal prisms, respectively. C-Sm2S! 90 Se, 10 adopts the cubic 7 -Ce2 S3-type structure (/ 43d; a = 858.7(2) pm, Z = 5.333) with trigon-dodecahedrally coordinated Snr + cations (CN = 8). Finally, U-Sm2S L84Se116 with the orthorhombic U2S3-type structure (Pnma; a = 1105.3(6), b = 399.2(1), c = 1074.0(5) pm, Z = 4) exhibits two crystallographically different Sm3+ cations again, which are coordinated by seven (Sml) and seven plus one (Sm2) Ch2_ anions, respectively. The preferential occupation of S _ and Se2-anions at only one in the C-type, but three anionic sites each in the A-and U-type crystal structures of Sm2 S2 -*Se1+;c (0 . 1 < x < 0 .2) is discussed. 
  Reference    Z. Naturforsch. 56b, 990—996 (2001); eingegangen am 14. Juni 2001 
  Published    2001 
  Keywords    Samarium, Sulfides, Selenides 
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 TEI-XML for    default:Reihe_B/56/ZNB-2001-56b-0990.pdf 
 Identifier    ZNB-2001-56b-0990 
 Volume    56 
2Author    Z. NaturforschRequires cookie*
 Title    Über Sulfide und Oxidsulfide des Samariums  
 Abstract    Stoichiometric oxidation o f SmCl2 with sulfur in the presence o f NaCl (evacuated silica ves­ sel, 850 °C, 7 d) results in the formation o f A -S m -,S 3 (orthorhombic, Pnma (no. 62), a = 737.64(5), b = 397.44(3), c = 1536.26(9) pm, Z = 4, /?w = 0.017). In contrast, C ~ S m 2S3 (cubic, I4 3 d (no. 220), a = 844.71(3) pm, Z = 5.333, Rw = 0.017) is obtained upon reaction o f the 
  Reference    Z. Naturforsch. 47b, 1614 (1992); eingegangen am 1. Juli 1992 
  Published    1992 
  Keywords    Samarium, Sulfides, Oxysulfides, Crystal Structure 
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 TEI-XML for    default:Reihe_B/47/ZNB-1992-47b-1614.pdf 
 Identifier    ZNB-1992-47b-1614 
 Volume    47 
3Author    Wolfgang RammRequires cookie*
 Title    Die Abhängigkeit der Absorption thermischer Neutronen von ihrer Geschwindigkeit  
 Abstract    Die Herabsetzung der Dichte thermischer Neutronen in der Umgebung eines Absorbers wurde bei Zimmertemperatur und bei 200 °C bestimmt. Daraus' konnte die Abhängigkeit des Einfangquerschnitts von der Energie im thermischen Gebiet, praktisch unabhängig von der Größe des Streuquerschnitts, gefunden werden. Die Messungen wurden mit Bor, 
  Reference    (Z. Naturforschg. 4a, 245—257 [1949]; eingegangen am 8. Mai 1948) 
  Published    1949 
  Keywords    Chlor, Mangan, Eisen, Kobalt, Kupfer, Silber, Cadmium, Samarium, Europium, Gadolinium, Dysprosium und Quecksilber durchgeführt 
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 TEI-XML for    default:Reihe_A/4/ZNA-1949-4a-0245.pdf 
 Identifier    ZNA-1949-4a-0245 
 Volume    4