No abstract

The manuscript posted describes the first use of 2D IR microscopy to spatially resolve chemical dynamics in a complex chemical environment. Full details of the 2D IR microscopy experiments, sample preparation, data analysis, and modeling are provided. The results reveal how chemical dynamics evolve across a room temperature ionic liquid microdroplet. In addition, this work demonstrates the power of 2D IR microscopy to quantitative information hidden by other chemical imaging approaches.

A major impediment limiting the widespread application of ionic liquids (ILs) is their high shear viscosity. Incorporation of a tricyanomethanide (TCM−) anion in ILs leads to low shear viscosity and improvement of several characteristics suitable for large scale applications. However, properties including interactions of TCM− with the local environment and dynamics of TCM− have not been thoroughly investigated. Herein, we have studied the ultrafast dynamics of TCM− in several imidazolium ILs using linear IR and two-dimensional infrared spectroscopy techniques. The spectral diffusion dynamics of the CN stretching modes of TCM− in all ILs exhibit a nonexponential behavior with a short time component of ∼2 ps and a long time component spanning ∼9 ps to 14 ps. The TCM− vibrational probe reports a significantly faster relaxation of ILs compared to those observed previously using linear vibrational probes, such as thiocyanate and selenocyanate. Our results indicate a rapid relaxation of the local ion-cage structure embedding the vibrational probe in the ILs. The faster relaxation suggests that the lifetime of the local ion-cage structure decreases in the presence of TCM− in the ILs. Linear IR spectroscopic results show that the hydrogen-bonding interaction between TCM− and imidazolium cations in ILs is much weaker. Shorter ion-cage lifetimes together with weaker hydrogen-bonding interactions account for the low shear viscosity of TCM− based ILs compared to commonly used ILs. In addition, this study demonstrates that TCM− can be used as a potential vibrational reporter to study the structure and dynamics of ILs and other molecular systems.

Climate change is devastating global agricultural and economic systems. Nature-based solutions that promote conservation agriculture can address these challenges while mitigating climate change. We propose a pilot crop insurance and research program in the U.S. Northern Plains to promote practices that enhance farm soil health, income, and resilience while mitigating climate change. Such a program could inform nationwide adoption of such practices. We specifically propose eliminating requirements for fallow to insure wheat, funding development of regionally-adapted leguminous crops, and incentivizing whole farm insurance over single-crop yield-focused offerings to promote economic growth and climate-resilient practices. The policies extend across a spectrum of cost, legislative burden, political capital, and time-scales for implementation and impact, offering a balanced and gradual transition to conservation agriculture. Adopted jointly, these recommendations improve farm resilience to climate change by promoting soil health and crop diversification while reducing emissions.

The manuscript posted describes the first use of 2D IR microscopy to spatially resolve chemical dynamics in a complex chemical environment. Full details of the 2D IR microscopy experiments, sample preparation, data analysis, and modeling are provided. The results reveal how chemical dynamics evolve across a room temperature ionic liquid microdroplet. In addition, this work demonstrates the power of 2D IR microscopy to quantitative information hidden by other chemical imaging approaches.