TY - JOUR
T1 - Contribution of disulfide S22- anions to the crystal and electronic structures in ternary sulfides, Ba12In 4S19, Ba4M2S8 (M = Ga, In)
AU - Liu, Ji Wei
AU - Wang, Peng
AU - Chen, Ling
PY - 2011/6/20
Y1 - 2011/6/20
N2 - Three semiconducting ternary sulfides have been synthesized from the mixture of elements with about 20% excess of sulfur (to establish oxidant rich conditions) by solid-state reactions at high temperature. Ba12In 4S19 (Ba2+)12(In3+) 4(S2-)17(S2)2-, 1, crystallizes in the trigonal space group R3 with a = 9.6182(5) Å, b = 9.6182(5) Å, c = 75.393(7) Å, and Z = 6, with a unique long period-stacking structure of a combination of monometallic InS4 tetrahedra, linear dimeric In2S7 tetrahedra, disulfide S22- anions, and isolated sulfide S2- anions that is further enveloped by Ba2+ cations. Ba4In 2S8 (Ba2+)4(In3+) 2(S2-)6(S2)2-, 2, crystallizes in the triclinic space group P1 with a = 6.236(2) Å, b = 10.014(4) Å, c = 13.033(5) Å, α = 104.236(6)°, β = 90.412(4)°, γ = 91.052(6)°, and Z = 2. Ba4Ga 2S8 (Ba2+)4(Ga3+) 2(S2-)6(S2)2-, 3, crystallizes in the monoclinic P21/c with a = 12.739(5) Å, b = 6.201(2) Å, c = 19.830(8) Å, β = 104.254(6)° and Z = 4. Compounds 2 and 3 represent the first one-dimensional (1D) chain structure in ternary Ba/M/S (M = In, Ga) systems. The optical band gaps of 1 and 3 are measured to be around 2.55 eV, which agrees with their yellow color and the calculation results. The CASTEP calculations also reveal that the disulfide S22- anions in 1-3 contribute mainly to the bottom of the conduction bands and the top of valence bands, and thus determine the band gaps.
AB - Three semiconducting ternary sulfides have been synthesized from the mixture of elements with about 20% excess of sulfur (to establish oxidant rich conditions) by solid-state reactions at high temperature. Ba12In 4S19 (Ba2+)12(In3+) 4(S2-)17(S2)2-, 1, crystallizes in the trigonal space group R3 with a = 9.6182(5) Å, b = 9.6182(5) Å, c = 75.393(7) Å, and Z = 6, with a unique long period-stacking structure of a combination of monometallic InS4 tetrahedra, linear dimeric In2S7 tetrahedra, disulfide S22- anions, and isolated sulfide S2- anions that is further enveloped by Ba2+ cations. Ba4In 2S8 (Ba2+)4(In3+) 2(S2-)6(S2)2-, 2, crystallizes in the triclinic space group P1 with a = 6.236(2) Å, b = 10.014(4) Å, c = 13.033(5) Å, α = 104.236(6)°, β = 90.412(4)°, γ = 91.052(6)°, and Z = 2. Ba4Ga 2S8 (Ba2+)4(Ga3+) 2(S2-)6(S2)2-, 3, crystallizes in the monoclinic P21/c with a = 12.739(5) Å, b = 6.201(2) Å, c = 19.830(8) Å, β = 104.254(6)° and Z = 4. Compounds 2 and 3 represent the first one-dimensional (1D) chain structure in ternary Ba/M/S (M = In, Ga) systems. The optical band gaps of 1 and 3 are measured to be around 2.55 eV, which agrees with their yellow color and the calculation results. The CASTEP calculations also reveal that the disulfide S22- anions in 1-3 contribute mainly to the bottom of the conduction bands and the top of valence bands, and thus determine the band gaps.
UR - http://www.scopus.com/inward/record.url?scp=79958843015&partnerID=8YFLogxK
U2 - 10.1021/ic2004936
DO - 10.1021/ic2004936
M3 - Article
AN - SCOPUS:79958843015
SN - 0020-1669
VL - 50
SP - 5706
EP - 5713
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 12
ER -