Recovering experimental and theoretical electron densities in corundum using the multipolar model: IUCr Multipole Refinement Project.

摘要: This electron-density study on corundum (α-Al2O3) is part of the Multipole Refinement Project supported by IUCr Commission Charge, Spin and Momentum Densities. For this purpose, eight different data sets (two experimental six theoretical) were chosen from which electron density was derived multipolar refinement (using MOLLY program). The two collected a conventional CAD4 at ESRF, ID11 with CCD detector, respectively. theoretical consist static, dynamic, static noisy dynamic moduli structure factors calculated Hartree–Fock (HF) functional theory (DFT) levels. Comparisons deformation residual densities show that analysis works satisfactorily but also indicate some drawbacks in refinement. Some solutions improvements during refinements are proposed like contraction or expansion inner atomic shells increasing order spherical harmonic expansion.