The prevalence of transition metal-mediated hydride transfer reactions in chemical synthesis, catalysis, and biology has inspired the development of methods for characterizing the reactivity of transition metal hydride complexes. Thermodynamic hydricity represents the free energy required for heterolytic cleavage of the metal–hydride bond to release a free hydride ion, H⁻, as determined through equilibrium measurements and thermochemical cycles. Kinetic hydricity represents the rate of hydride transfer from one species to another, as measured through kinetic analysis. This tutorial review describes the common methods for experimental and computational determination of thermodynamic and kinetic hydricity, including advice on best practices and precautions to help avoid pitfalls. The influence of solvation on hydricity is emphasized, including opportunities and challenges arising from comparisons across several different solvents. Connections between thermodynamic and kinetic hydricity are discussed, and opportunities for utilizing these connections to rationally improve catalytic processes involving hydride transfer are highlighted.

中文翻译：

---

过渡金属氢化物的热力学和动力学水合度。

过渡金属介导的氢化物转移反应在化学合成，催化和生物学中的普遍应用激发了表征过渡金属氢化物配合物反应性方法的发展。热力学水合表示金属-氢键的杂合裂解以释放自由氢离子H-所需的自由能^。通过平衡测量和热化学循环确定。动力学羟基表示氢化物从一种物质转移到另一种物质的速率，通过动力学分析测量。本教程概述描述了通过实验和计算方法确定热力学和动力学水合度的常用方法，包括有关最佳实践和预防措施的建议，以帮助避免陷阱。强调了溶剂化对水合度的影响，包括通过对几种不同溶剂进行比较而产生的机遇和挑战。讨论了热力学和动力学水力之间的联系，并着重介绍了利用这些联系合理地改善涉及氢化物转移的催化过程的机会。