保持层间距但失去堆叠顺序的层状物质
Layered matter that maintains spacing but loses stacking order
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中文总结 AI 辅助
该研究发现刚性带电纳米片溶胀悬浮液中层间距与堆叠有序度可解耦，层间距可通过盐度调控，堆叠仅2至3层，此行为为首次观测的本征低维周期序类老化弛豫，适用于多种刚性溶胀纳米片体系。
中文摘要 AI 辅助
在层状材料中，层间距与堆叠有序度通常相互关联。本文表明，在刚性带电纳米片的溶胀悬浮液中，二者会解耦，形成区别于这类体系通常所处的晶态和维格纳溶胀态的独特区域。平均层间距保持尖锐且可通过盐度调控，而散射权重加权的堆叠仅覆盖2至3层。我们在近乎完美的模型材料中证实了这一行为，说明其是本征的而非缺陷驱动的。X射线与中子散射、沉降及唐南分析显示，层间距由低于1帕/纳米的无参数渗透恢复斜率维持。由于该斜率极弱，层间距处于平衡状态，而缺陷会缓慢弛豫，形成淬灭的亚稳态配准，其低维周期序的类老化弛豫据我们所知此前尚未实现。预计从黏土到氧化物纳米片、氧化石墨烯等各类刚性溶胀纳米片体系均存在此类解耦现象。
英文摘要
In layered materials, spacing and stacking-order extent are usually locked. Here we show that in swollen suspensions of stiff, charged nanosheets they decouple, and that this defines a distinct regime, apart from the crystalline- and Wigner-swelling regimes such systems usually occupy. The mean spacing stays sharp and salinity-tunable while scattering-weighted stacking spans only two to three layers. We demonstrate this in a near-perfect model material, so the behaviour is intrinsic, not defect-driven. X-ray and neutron scattering, sedimentation and a Donnan analysis show the spacing is held by a parameter-free osmotic restoring slope below one pascal per nanometre. Because the slope is so weak, the spacing sits at equilibrium while faults relax slowly, a quenched metastable registry whose ageing-like relaxation of low-dimensional periodic order has not, to our knowledge, been realised before. The same decoupling is expected across stiff, swollen nanosheets, from clays to oxide nanosheets and graphene oxide.
