A New Boron Allotrope, Imma-B60: Deformable and a Million Times More Conductive

The team prepared a previously unrealized boron allotrope, Imma-B60, with electrical conductivity more than a million times that of typical boron materials and with deformability. Since the last discovery of an unusual boron allotrope in 2009, almost no new boron allotropes had been found experimentally despite many predictions, so this structure fills a 16-year experimental gap. The report states the structure was published in Nature Chemistry and gives a specific preparation route plus mechanical and electrical properties; however, the homepage evidence bundle is a summary-level read without the full paper, figures, or data tables.

Preparation used a two-step process: boron was first reacted with sodium under high pressure, then heated at 400 °C under vacuum to almost completely remove sodium impurities, yielding Imma-B60. This two-step process had never before been applied to boron, and the report quotes Oganov calling it 'a powerful approach — not brand new but perhaps the most elegant, most modern application of it.' The method description specifies elements, pressure conditions, and temperature, but gives no pressure values, yield, or quantitative purity metrics.

Imma-B60 consists of a network of boron atoms with open space where sodium atoms used to be, enabling a movement of atoms called dislocation slip; the material is therefore deformable, extending to 23% of its original length before breaking and not bouncing back once extended. Typical boron materials are superhard and mostly poorly conducting, whereas this phase combines deformability with high conductivity, a property combination unlike existing boron phases. The report gives the specific figure of 23% extension, but does not state test conditions, sample dimensions, or statistical replication.

Oganov, who was involved in the 2009 work, sees this discovery as opening a synthesis route for an entire family of materials. It links the synthesis of a single new phase to a route toward 'an entire family of materials,' pointing to a potentially extensible preparation direction. This is an expert commentary judgment rather than experimental data itself; the report gives no evidence that other members of that family have been synthesized.

This result applies to the Imma-B60 phase synthesized under high-pressure sodium-assisted conditions and then vacuum-desodiated at 400 °C; its deformability and high conductivity were observed for this specific structure and preparation path. The report frames it as the start of a synthesis route toward 'an entire family of materials,' so its significance is aimed primarily at researchers pursuing further experimental exploration of boron allotropes and related materials rather than at direct device applications.

The homepage evidence bundle is a summary-level read without the full paper, figures, or data tables, so specific pressure values, yield and purity, how conductivity was measured, the conditions of the extension test, and sample scale cannot be confirmed from the available text; moreover, the prospect of synthesizing 'an entire family of materials' currently comes from expert commentary rather than a completed series of syntheses, leaving its extensibility an open question to watch.