TY - JOUR

T1 - High-pressure anisotropic distortion of Pb3Bi2S6

T2 - a pressure-induced, reversible phase transition with migration of chemical bonds

AU - Olsen, Lars Arnskov

AU - Balic Zunic, Tonci

AU - Makovicky, Emil

PY - 2008

Y1 - 2008

N2 - The compound Pb3Bi2S6 is investigated by X-ray diffraction on single crystals in a diamond-anvil cell between 0.0001 and 10.5 GPa. It undergoes a first-order phase transition at hydrostatic pressure between 3.7 and 4.9 Gpa. The space group symmetry changes from Bbmm to Pbnm, and the unit-cell volume decreases by 4%. The transition is strongly anisotropic, with a contraction along one of the crystal axes by 16% and expansion along another one by 14%. This is a piezoplastic phase transition, a displacive pressure-induced phase transition with systematic shearing of atomic planes and a migration of chemical bonds in the structure. In the case of Pb3Bi2S6 the transition is achieved by the change of the archetypal architecture of the structure-building modules from a PbS-like to  SnS-like arrangement and a loss of mirror planes on the contact surfaces of modules. The phase transition is reversible with a preservation of the single crystal, which is a result of the stereochemical influence and migration of the s2 lone electron pairs of PbII and BiIII.   

AB - The compound Pb3Bi2S6 is investigated by X-ray diffraction on single crystals in a diamond-anvil cell between 0.0001 and 10.5 GPa. It undergoes a first-order phase transition at hydrostatic pressure between 3.7 and 4.9 Gpa. The space group symmetry changes from Bbmm to Pbnm, and the unit-cell volume decreases by 4%. The transition is strongly anisotropic, with a contraction along one of the crystal axes by 16% and expansion along another one by 14%. This is a piezoplastic phase transition, a displacive pressure-induced phase transition with systematic shearing of atomic planes and a migration of chemical bonds in the structure. In the case of Pb3Bi2S6 the transition is achieved by the change of the archetypal architecture of the structure-building modules from a PbS-like to  SnS-like arrangement and a loss of mirror planes on the contact surfaces of modules. The phase transition is reversible with a preservation of the single crystal, which is a result of the stereochemical influence and migration of the s2 lone electron pairs of PbII and BiIII.   

KW - Faculty of Science

KW - Pb3Bi2S6

KW - high pressure anisotopic distortion

KW - Pb3Bi2S6

KW - chemical bonds

M3 - Journal article

VL - 47

SP - 6756

EP - 6762

JO - Inorganic Chemistry

JF - Inorganic Chemistry

SN - 0020-1669

ER -