10.1021/cm400858d.s014 Carl K. Brozek Carl K. Brozek Anthony F. Cozzolino Anthony F. Cozzolino Simon J. Teat Simon J. Teat Yu-Sheng Chen Yu-Sheng Chen Mircea Dincă Mircea Dincă Quantification of Site-Specific Cation Exchange in Metal–Organic Frameworks Using Multi-Wavelength Anomalous X‑ray Dispersion American Chemical Society 2016 cation exchange Mn heterometallic MOFs K edges dispersion metal sites dispersive differences Fe cation occupation Zn extent method data BTT Cu 2016-02-19 01:17:06 Dataset https://acs.figshare.com/articles/dataset/Quantification_of_Site_Specific_Cation_Exchange_in_Metal_Organic_Frameworks_Using_Multi_Wavelength_Anomalous_X_ray_Dispersion/2387860 We employed multiwavelength anomalous X-ray dispersion to determine the relative cation occupation at two crystallographically distinct metal sites in Fe<sup>2+</sup>-, Cu<sup>2+</sup>-, and Zn<sup>2+</sup>-exchanged versions of the microporous metal–organic framework (MOF) known as MnMnBTT (BTT = 1,3,5-benzenetristetrazolate). By exploiting the dispersive differences between Mn, Fe, Cu, and Zn, the extent and location of cation exchange were determined from single crystal X-ray diffraction data sets collected near the K edges of Mn<sup>2+</sup> and of the substituting metal, and at a wavelength remote from either edge as a reference. Comparing the anomalous dispersion between these measurements indicated that the extent of Mn<sup>2+</sup> replacement depends on the identity of the substituting metal. We contrasted two unique methods to analyze this data with a conventional approach and evaluated their limitations with emphasis on the general application of this method to other heterometallic MOFs, where site-specific metal identification is fundamental to tuning catalytic and physical properties.