Issue 41, 2022

Polymorphism and solid solutions of trimethylammonium monocarboranes

Abstract

Metal closo-boranes have recently received significant attention as solid-state electrolytes due to their high thermal and electrochemical stability, and the weak interaction between the cat- and anion, facilitating fast ionic conductivity. Here we report a synthesis method for obtaining a novel mixed closo-carborane compound, [NH(CH3)3][(CB8H9)0.26(CB9H10)0.66(CB11H12)0.08]. The crystal structures are investigated for [NH(CH3)3][CB9H10] and [NH(CH3)3][(CB8H9)0.26(CB9H10)0.66(CB11H12)0.08], revealing that the latter forms a solid solution isostructural to [NH(CH3)3][CB9H10]. The compounds exhibit polymorphism as a function of temperature, and we report the discovery of four polymorphs of [NH(CH3)3][CB9H10] and four isostructural solid solution [NH(CH3)3][(CB8H9)0.26(CB9H10)0.66(CB11H12)0.08], along with a high-temperature decomposition intermediate of the latter. The α-polymorph is an ordered structure, with increasing amounts of disorder for the β- and γ-polymorphs, while the high temperature δ- and ε-polymorphs at T > 476 K are fully disordered on both the cation and anion site. These new compounds may be used as precursors for new types of solid-state ionic conductors.

Graphical abstract: Polymorphism and solid solutions of trimethylammonium monocarboranes

Supplementary files

Article information

Article type
Paper
Submitted
02 8 2022
Accepted
26 9 2022
First published
27 9 2022

Dalton Trans., 2022,51, 15806-15815

Polymorphism and solid solutions of trimethylammonium monocarboranes

J. B. Grinderslev, L. N. Skov, D. R. Sørensen, I. Kantor, M. R. V. Jørgensen and T. R. Jensen, Dalton Trans., 2022, 51, 15806 DOI: 10.1039/D2DT02513B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements