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Recent advances in the development of perovskite based solar cells have increased the demand for in-depth characterisation of the perovskite structures and the dynamics of their various constituents in relation to the potential impact on the photovoltaic performance. NMR can play an important role in this respect; NMR has been used to study the incorporation of different ionic species, characterize their internal dynamics and diffusion, and monitor the chemical stability of these technologically relevant materials, including upcoming lower dimensional perovskite materials. Furthermore, the flexibility of NMR allows the study of the materials under relevant conditions e.g. under illumination. Here we present an overview of the recent literature on NMR of (hybrid) halide perovskites, focusing on the insights that NMR can provide.

Objectives Cardiovascular diseases and exercise intolerance elevate mortality in type 1 diabetes (T1D). Left ventricular systolic and diastolic function are already affected in T1DM adolescents, displaying poor glycemic control (glycated hemoglobin [A1C]>7.5%) and exercise intolerance. We investigated to the extent to which left ventricular function is affected by disease severity/duration and whether this is related to exercise capacity. Methods Transthoracic echocardiography was performed in 19 T1DM adolescents (14.8±1.9 years old, A1C 7.4±0.9%) and 19 controls (14.4±1.3 years old, A1C 5.3±0.2%), matched for age and Tanner stage. Diastolic and systolic (ejection fraction [EF]) function were assessed. Cardiopulmonary exercise testing was used to evaluate exercise capacity, as measured by peak oxygen uptake (VO2peak). Results VO2peak and left ventricular systolic and diastolic function were similar in both groups. Within the T1D group, EF was negatively associated with disease duration (r=−0.79 corrected for age, standardized body mass index, glucose variability and VO2peak; p=0.011). Regression analyses revealed that 37.6% of the variance in EF could be attributed to disease duration. Conclusions Although left ventricular systolic and diastolic function are preserved in T1D with adequate exercise capacity, disease duration negatively affects EF. The detrimental effects of T1D seem to be driven by disease duration, rather than by disease severity, at least during adolescence. Young T1D patients may, therefore, benefit from cardiovascular evaluation in order to detect cardiovascular abnormalities early in the disease course, and therefore, improve long-term cardiovascular health.

In this contribution we used solid state 35 Cl ( I = 3/2) quadrupolar NMR to study a MgCl 2 /2,2-dimethyl-1,3-dimethoxypropane (DMDOMe) adduct that serves as a model system for Ziegler-Natta catalysis. Employing large Radio-Frequency (RF) field strengths we observe three spectral features with strongly varying line widths. The assignment of the spectra is complicated because of the large difference in quadrupolar interactions experienced by the different sites in the system. The satellite transitions (ST) of relatively well-defined bulk Cl sites are partially excited and may overlap with the central transition (CT) resonances of more distorted surface sites. We show that nutation NMR of the ST of I = 3/2 spins yields a unique pattern that makes a clear distinction between an extensively broadened central transition and the satellite transitions of a component with a smaller quadrupolar interaction. This allows us to unambiguously unravel the spectra of the MgCl 2 adduct showing that we observe CT and ST of the bulk phase of MgCl 2 -nanoparticles with a C Q of 4.6 MHz together with the CT of surface sites displaying an average C Q of ∼ 10 MHz.