A novel approach for precise density measurement of small samples with a weight in the mg-range has been developed recently [1]. Using this approach, a solid object is dropped into a semi-confined cylindrical cavity, which is filled with a nonvolatile liquid. To determine the volume of the sample the rise of the liquid meniscus is measured with confocal microscopy. During the development of new MOFs, the lack of an appropriate amount of material makes it often impossible to determine the bulk density of the new material. Here we demonstrate how the density of small MOF samples can be determined by this novel method. Even with samples in the range of 1.5 mg we can measure the density with an accuracy better than 1%. The effect of previous sorption of other liquids and the distinction of open and closed porosity will be addressed.

1.: Bulk Density Measurements of Small Solid Objects Using Laser Confocal Microscopy. A. Kilmametov, R. Gröger, H. Hahn, Th. Schimmel and S. Walheim: Advanced Materials Technology 2017, 2, 1600115