Abstract
The effect of Fourier series truncation errors on the electron density distribution (EDD) of LiMn2O4 has been examined using the single-crystal synchrotron X-ray diffraction data and the molecular dynamics (MD) simulation. The MD crystal structure factors obtained from each MD snapshot taken at 2fs intervals in real space were time-averaged and then reversely Fourier transformed to calculate EDD in a similar way to the X-ray data. The EDD thus obtained in the range sin\q/\l < 3.33 Å-1 was scarcely affected by the series truncation errors, indicating unambiguously that a small portion of Li does exist close to interstitial positions near the 16c site of the space group Fd-3m. The residual EDD assuming a partial structure with eliminating Li atoms also reproduced a mostly correct picture about the distribution of interstitial Li atoms, even though the value of sin\q/\l of the MD data was reduced to 0.80 A-1. The interpretation of EDD obtained from the single-crystal synchrotron X-ray diffraction data was thus verified and reinforced from the MD simulation, not only by looking at the real space distribution of atoms in the snapshots but also by a close examination of their Fourier transform.
