Bond-valence parameters for characterizing O-H⋯O hydrogen bonds in hydrated borates

The bond-valence parameters d0 of homonuclear O-H⋯O hydrogen bonds in hydrated borates are investigated on the basis of the crystallographic data available in the Inorganic Crystal Structure Database (2004 release). Using two different approaches (based on Coulomb's law and Golden ratio, respectively), our present work can strongly support the conclusion that bond-valence parameters d0 are linearly correlated to the corresponding bond lengths of hydrogen bonds. A design route for inorganic crystals is suggested when comparing and analyzing these two methods, which may be of some benefit to understanding the important role of the bond-valence parameter d0 in structurally designing crystals with hydrogen bonds.