TY - JOUR
T1 - AuPb2I7
T2 - A Narrow Bandgap Au3+ Iodide Semiconductor
AU - Alexander, Grant C.B.
AU - Fabini, Douglas H.
AU - Seshadri, Ram
AU - Kanatzidis, Mercouri G.
N1 - Funding Information:
Optical Absorption and Electronic Structure. The bandgap of black AuPb2I7 was determined to be 1.17 eV by UV−vis diffuse-reflectance spectroscopy measurements, Figure 9. Here, optical absorption is dominated by metal−ligand charge transfer transitions within the [AuI4]− unit; thus, it acts as a strong chromophore. This interpretation is supported by the DFT calculations below.
Publisher Copyright:
© 2018 American Chemical Society.
PY - 2018/1/16
Y1 - 2018/1/16
N2 - The unusual Au3+ ternary halide AuPb2I7 has been isolated from reactions of AuI, PbI2, and I2. AuPb2I7 crystallizes in the triclinic P1̄ space group as micron-scale needles with cell dimensions a = 4.5170(3) Å, b = 7.3847(4) Å, c = 12.2970(7) Å, α = 76.374(4)°, β = 83.711(4)°, γ = 72.987(3)° at room temperature with p = 6.538 g/cm3 and has no structural phase transition down to 100 K. The title compound has a unique three-dimensional structure composed of [Pb2I7]3- pseudolayers extending in [010] bridged by square planar Au3+ at an oblique angle in the [001] direction. The pseudolayers are composed of 1/∞[Pb2I2]2+ chains propagating down [100] linked by square planar I- ions through [010]. AuPb2I7 has a bandgap of 1.17 eV and is stable in air for several days, before degrading to PbI2, Au0, and I2. Density functional theory calculations show that AuPb2I7 is an indirect bandgap semiconductor where the bandgap stems predominantly from Au-I metal-ligand charge transfer.
AB - The unusual Au3+ ternary halide AuPb2I7 has been isolated from reactions of AuI, PbI2, and I2. AuPb2I7 crystallizes in the triclinic P1̄ space group as micron-scale needles with cell dimensions a = 4.5170(3) Å, b = 7.3847(4) Å, c = 12.2970(7) Å, α = 76.374(4)°, β = 83.711(4)°, γ = 72.987(3)° at room temperature with p = 6.538 g/cm3 and has no structural phase transition down to 100 K. The title compound has a unique three-dimensional structure composed of [Pb2I7]3- pseudolayers extending in [010] bridged by square planar Au3+ at an oblique angle in the [001] direction. The pseudolayers are composed of 1/∞[Pb2I2]2+ chains propagating down [100] linked by square planar I- ions through [010]. AuPb2I7 has a bandgap of 1.17 eV and is stable in air for several days, before degrading to PbI2, Au0, and I2. Density functional theory calculations show that AuPb2I7 is an indirect bandgap semiconductor where the bandgap stems predominantly from Au-I metal-ligand charge transfer.
UR - http://www.scopus.com/inward/record.url?scp=85044640509&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85044640509&partnerID=8YFLogxK
U2 - 10.1021/acs.inorgchem.7b02723
DO - 10.1021/acs.inorgchem.7b02723
M3 - Article
C2 - 29292998
AN - SCOPUS:85044640509
VL - 57
SP - 804
EP - 810
JO - Inorganic Chemistry
JF - Inorganic Chemistry
SN - 0020-1669
IS - 2
ER -