Darstellung, ¹¹B-NMR- und Schwingungsspektren isomerenreiner Halogenohydrododecaborate X_nB₁₂H_12–n ^2–; X = Cl, n = 1–3; X = Br, n = 1,2; X = I, n = 1 / Preparation, nB NMR and Vibrational Spectra of Pure Isomeric Halohydrododecaborates X_nB₁₂H_12-n ^2-; X = Cl, n = 1-3; X = Br, n = 1,2; X = I, n = 1

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Open Access

1 February 1984

journal article
research article
Published by Walter de Gruyter GmbH in Zeitschrift für Naturforschung B

Vol. 39 (2) , 189-196
DOI:10.1515/znb-1984-0212

Abstract

Pure isomers of X_nB₁₂H_12-n ^2-; X = Cl, Br, I are isolated by ion exchange chromatography on diethylaminoethyl cellulose. The structures are determined by ¹¹B and ¹¹B {¹H}NMR spectroscopy. With X = Cl, Br the signal of ipso-B atomes is shifted to lower, with X = I to higher field compared with B₁₂H₁₂ ^2-. The resonances of B-atoms influenced by the antipodal effect are observed at high field, increasing within the series I12H₁₂ ^2- with chlorine proceeds successively at vicinal positions B(1) -B(2) -B(3). The IR and Raman spectra of 1-XB₁₂H₁₁ ^2- show in the region 175 - 380 cm ^-1 two characteristic bands shifting to lower frequencies in the series Cl, Br, I and are therefore assigned to (B₁₂) -X stretching and (B₁₂) -X bending modes, respectively

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