Increasing the polarity of the reaction medium by the addition of 5-10% of methanol to the DMF resulted in an isohedral form. This observation shows that there is a family of closely related crystals forms, not all of which are evidently chiral (Fig. ). The angles between faces within the {122} and {111 % } forms, and between the {212} and {111 % } forms, were measured from micro-CT data as 45(4)°, 49(4)° and 55(4)°. The theoretical values are 52°, 52° and 55°, respectively. The peaks of the pyramids computed from angle between top opposing pairs of facets and bottom opposing pairs of facets were 56° and 45°, respectively. These angles matched those of micrographs analyzed in projection as in Fig. . The "offsets" of top and bottom pyramids with different amounts of methanol are shown in Fig. The optical anisotropy of the crystals with the optic axes lying at an angle to the optical path was indicated by the linear retardance (LR) between crossed polarizers (Fig. ). The crystals resemble quartz wedge compensators displaying many orders of interference colors with increasing path length. The crystals were extinct (dark) when the long axis (hexagonal optic axis) was parallel or perpendicular to the preferred plane of the polarizer and wave vector. Channels identified in the X-ray structure (vide infra) were established chemically. Immersing the crystals in a methanol solution containing a commonly used fluorophore, sodium resorufin (Fig. ), resulted in dye inclusion crystals. 3D fluorescence microscophs show the homogeneous distribution of the red luminescence arising from the excitation of the purple resorufin fluorophore in the crystal (Fig. ). The resulting crystals are purple with a polarizer parallel to the long axes of the bipyramids and colorless in the orthogonal orientation (Fig. ). This complete linear dichroism is consistent with the resorufin ring system with a long axis transition moment in the visible part of the spectrum aligned along the hexagonal c-axis of the MOF channels.