Molecules (Aug 2004)
Studies on TMPD:TCNB; a Donor-Acceptor with Room Temperature Paramagnetism and n-À Interactionâ€
Abstract
A donor-acceptor compound based on N,N,N′,N′-tetramethyl-p-phenylene-diamine and 1,2,4,5-tetracyanobenzene (TMPD:TCNB) has been synthesized. The crystalstructure of the black 1:1 complex formed between TMPD and TCNB has beendetermined by single crystal X-ray diffraction at room temperature. The compoundcrystallizes in the triclinic space group P-1 with cell dimensions: a = 7.4986(15) Ã¥, b =7.6772(11) Ã¥, c = 8.0764(15) Ã¥, α = 78.822(12)°, β = 83.3779(19)°, γ = 86.289(17)°.TMPD and TCNB molecules are stacked alternately in infinite columns along the a-axis.The structure does not seem to show the usual À-À interaction between the two aromaticrings, but indicates an n-À interaction localized between the nitrogen atoms of the donorand the cyano groups of the acceptor.
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