对富含硅 - 29 和氮 - 15 的氮化硅进行的固态核磁共振研究。

Solid-state NMR investigations of Si-29 and N-15 enriched silicon nitride.

作者信息

Leonova Ekaterina, Grins Jekabs, Shariatgorji Mohammadreza, Ilag Leopold L, Edén Mattias

机构信息

Physical Chemistry Division, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden.

出版信息

Solid State Nucl Magn Reson. 2009 Sep;36(1):11-8. doi: 10.1016/j.ssnmr.2009.03.001. Epub 2009 Mar 20.

DOI:10.1016/j.ssnmr.2009.03.001

PMID:19394802

Abstract

We compare (29)Si magic-angle spinning (MAS) nuclear magnetic resonance (NMR) spectra from the two modifications of silicon nitride, alpha-Si(3)N(4) and beta-Si(3)N(4), with that of a fully ((29)Si, (15)N)-enriched sample (29)Si(3)(15)N(4), as well as (15)N NMR spectra of Si(3)(15)N(4) (having (29)Si at natural abundance) and (29)Si(3)(15)N(4). We show that the (15)N NMR peak-widths from the latter are dominated by J((29)Si-(15)N) through-bond interactions, leading to significantly broader NMR signals compared to those of Si(3)(15)N(4). By fitting calculated (29)Si NMR spectra to experimental ones, we obtained an estimated coupling constant J((29)Si-(15)N) of 20Hz. We provide (29)Si spin-lattice (T(1)) relaxation data for the (29)Si(3)(15)N(4) sample and chemical shift anisotropy results for the (29)Si site of beta-Si(3)N(4). Various factors potentially contributing to the (29)Si and (15)N NMR peak-widths of the various silicon nitride specimens are discussed. We also provide powder X-ray diffraction (XRD) and mass spectrometry data of the samples.

摘要

我们将氮化硅的两种变体α-Si(3)N(4)和β-Si(3)N(4)的（29）Si魔角旋转（MAS）核磁共振（NMR）光谱与完全（（29）Si，（15）N）富集的样品（29）Si(3)(15)N(4)的光谱进行比较，以及Si(3)(15)N(4)（天然丰度的（29）Si）和（29）Si(3)(15)N(4)的（15）N NMR光谱。我们表明，后者的（15）N NMR峰宽主要由J（（29）Si-（15）N）通过键相互作用决定，导致与Si(3)(15)N(4)相比，NMR信号明显更宽。通过将计算的（29）Si NMR光谱与实验光谱拟合，我们得到了估计的耦合常数J（（29）Si-（15）N）为20Hz。我们提供了（29）Si(3)(15)N(4)样品的（29）Si自旋晶格（T(1)）弛豫数据以及β-Si(3)N(4)的（29）Si位点的化学位移各向异性结果。讨论了可能导致各种氮化硅样品的（29）Si和（15）N NMR峰宽的各种因素。我们还提供了样品的粉末X射线衍射（XRD）和质谱数据。