Mapping the Basicity of Selected 3d and 4d Metal Nitrides: A DFT Study
Mapping the Basicity of Selected 3d and 4d Metal Nitrides: A DFT Study
复制标题
绘制选定 3d 和 4d 金属氮化物的碱度图：DFT 研究
DOI：
10.1021/acs.inorgchem.2c01812
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发表时间：
2022
影响因子：
4.6
通讯作者：
Cundari, Thomas R.
中科院分区：
文献类型：
--
作者：
Alharbi, Waad S.;Cundari, Thomas R.
氮化物络合物在各种转化中被用作催化剂和中间体，并以其可调的酸/碱性质而闻名。本文报道了密度泛函理论研究，其绘制了常规形成氮化物络合物的3d和4d过渡金属的碱度：V、Cr、Mn、Nb、Mo、Tc和Ru。从剑桥结构数据库收集络合物，并从质子化的自由能计算氮化物基团的pKb（N），以量化金属身份、氧化态、配位数和支持配体类型对金属-氮化物碱度的影响。一般来说，过渡金属氮化物的碱度在3d和4d行上从左到右减小，并且从3d金属到它们的4d同系物增加。金属特性和氧化态主要决定碱度趋势;然而，支持配体类型对给定金属的碱度范围有重大影响。这些因素在确定整体pKb（N）值的协同作用进行了讨论，因为是金属氮化物的催化反应性的影响。
Nitride complexes have been invoked as catalysts and intermediates in a wide variety of transformations and are noted for their tunable acid/base properties. A density functional theory study is reported herein that maps the basicity of 3d and 4d transition metals that routinely form nitride complexes: V, Cr, Mn, Nb, Mo, Tc, and Ru. Complexes were gathered from the Cambridge Structural Database, and from the free energy of protonation, the pKb(N) of the nitride group was calculated to quantify the impact of metal identity, oxidation state, coordination number, and supporting ligand type upon metal-nitride basicity. In general, the basicity of transition metal nitrides decreases from left to right across the 3d and 4d rows and increases from 3d metals to their 4d congeners. Metal identity and oxidation state primarily determine basicity trends; however, supporting ligand types have a substantial impact on the basicity range for a given metal. Synergism of these factors in determining the overall pKb(N) values is discussed, as are the implications for the catalytic reactivity of metal nitrides.