Adjustment of twist angles in pseudo-helical lanthanide complexes by the size of metal ions

Shin Mizukami, Hirohiko Houjou, Masatoshi Kanesato, Kazuhisa Hiratani

Research output: Contribution to journalArticlepeer-review

69 Citations (Scopus)


Control of self-assembled nanostructures is a promising technique for nanotechnology. We have examined as to whether nanostructures could be controlled by the size of the central metal ion. Lanthanides are a natural choice for such a study as the size of their trivalent ions changes with atomic number gradually. For this investigation, a series of rare earth complexes ([LaL1], [CeL1], [SmL1], [TUL1], [YL1], and [LuL1]) with a tripodal heptadentate ligand L1 were synthesized, and their X-ray crystallographic analysis was performed. Although the structures of the ligand (H3L1) and of the metal complex ([ML1]) were quite different, all complexes were almost isostructural pseudohelices. The result of the crystallographic studies demonstrated that the twist angles of helices in the complexes depend on the ionic size of the central metal. A detailed analysis helped determine which portion of the helical strand contributed to the total helicity, and the major cause for the difference in helicity among the lanthanides is discussed. Moreover, this result is the first example showing that LaIII and LuIII complexes with the same tripodal heptadentate ligand are isostractural.

Original languageEnglish
Pages (from-to)1521-1528
Number of pages8
JournalChemistry - A European Journal
Issue number7
Publication statusPublished - 2003 Apr 4
Externally publishedYes


  • Helical structures
  • Lanthanides
  • Structure elucidation
  • Twist angle

ASJC Scopus subject areas

  • Catalysis
  • Organic Chemistry


Dive into the research topics of 'Adjustment of twist angles in pseudo-helical lanthanide complexes by the size of metal ions'. Together they form a unique fingerprint.

Cite this