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Article

Diffuse Diffraction from Parallel/Antiparallel Metallocene Pillars

Supporting Info

Levi J. Irwin, Paul D. Zeits, Joseph H. Reibenspies, and Stephen A. Miller*

Department of Chemistry, Texas A&M University, College Station, Texas 77843-3255

Organometallics, 2007, 26 (5), pp 1129–1133

DOI: 10.1021/om060435g

Publication Date (Web): January 24, 2007

To whom correspondence should be addressed. E-mail: samiller@ mail.chem.tamu.edu.

Abstract

X-ray diffraction analyses of dimethyl ansa-metallocenes (CH₃)₂C(C₅H₄)(C₂₉H₃₆)M(CH₃)₂ (M = Zr or Hf) have revealed diffuse diffraction bands in the 0kl and h0l single-crystal reciprocal lattice images, but not in the hk0 plane. This is consistent with metallic disorder in two dimensions and constitutes a rare example of diffuse diffraction for an organometallic compound. The metal is apparently partitioned between two sites with a 60:40 occupancy ratio. Structural interpretation of the X-ray data is consistent with a 60:40 ratio of parallel/antiparallel (+z, −z) metallocene pillars dispersed in the x−y directions. Diffuse diffractionalbeit weakeris also observed for the half-metallocene (C₂₉H₃₇)Mn(CO)₃, which occupies parallel/antiparallel pillars in an 80:20 ratio.

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Published In Issue February 26, 2007
Received May 18, 2006

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Article

Diffuse Diffraction from Parallel/Antiparallel Metallocene Pillars