Novel triplet silavinylidenes via density functional theory

Following our quest for novel triplet silylenes, we have compared and contrasted electronic effects on 5‐silavinylidenyl‐1,4‐diX‐tetrazoles with XH, CH3, OCH3, NH2, NMe2, OH, CN, Cl, CF3, and F (1–10, respectively), at M06/6‐311++G** level of theory. Six structures with XH (1) and electron‐donating groups (EDGs, 2–6) appear triplet while the other four with electron‐withdrawing groups (EWGs, 7–10) show singlet ground states. The overall trend for triplet stability based on their ΔEs‐t is 1 > 2 > 3 > 4 > 5 > 6 > 7 > 8 > 9 > 10. The EWGs increase electrophilicity (ω) making 7 (7.09 eV) as the most electrophilic species. In contrast, EDGs increase nucleophilicity (N) showing 5 (5.47 eV) and 8 (3.18 eV) as the most and least nucleophilic silylenes, respectively. Moreover, 5 and 8 show the highest and lowest chemical potential (μ = −3.14 and −5.29 eV, respectively). In addition, 5 displays the highest energies of HOMO (EHOMO = −4.02 eV) and LUMO (ELUMO = −2.27 eV) and the lowest ω (2.82 eV) among the scrutinized species. We have reached for 5‐silavinylidenyl‐1,4‐diX‐tetrazoles with XH, CH3, OCH3, NH2, NMe2, OH, CN, Cl, CF3, and F (1–10, respectively), at M06/6‐311++G** level of theory. Among our scrutinized silavinylidenes, 1–6 appear triplet while 7–10 show singlet ground states.