The anion is tetrahedral with B-C bond lengths of approximately 1.65 Angstroms. Pore sizes typically range from ~10-100 Angstroms for 1K to 50K MWCO membranes. The diameter of an HHV-6 virion is about 2000 Angstroms. The unit cell of titanium disulfide is 3.407 by 5.695 angstroms. Direct-lattice vectors have components measured in distance units, like meters or angstroms. The active particles were about one hundred angstroms across. In calix[4]arenes the internal volume is around 10 cubic angstroms. Second, the two bilayers must come into very close contact (within a few angstroms). The gorge penetrates halfway through the enzyme and is approximately 20 angstroms long. The subunits form a cluster 70-80 Angstroms wide, which is then filled with iron ferrihydrite. The active site is located 4 angstroms from the bottom of the molecule. Its average bond length is 1.4 angstroms. O distances have been calculated to be 1.838(2) and 1.141(2) angstroms respectively. The Van der Waals forces are effective only up to several hundred angstroms.