Theoretical studies on ytterbium trichelates, Yb(L)3(L = trifluoromethanesulfonate (OTF), perchlorate (ClO4), p-toluenesulfonic (TOS), nitrobenzenesulfonic (NBSA), and dodecylsulfate (DOS), are carried out using density functional theory method at the PW91/TZP level, for the first time. All ligands are bidentate and the compounds exhibit a distorted trigonal prismatic structure, with a maximum twist angle obtained for ytterbium p-toluenesulfonic compound Yb(TOS)3. The quantum theory of atoms in molecules (AIM) and energy decomposition analysis reveal the dominant ionic character in ytterbium–oxygen bonding with a little covalent character. According to the Pearson terminology, the Yb(NBSA)3complex reveals the higher acidity. © 2012 Wiley Periodicals, Inc.