Abstract |
극성용매(L; ANT, MFA, DMSO, DMF, DMA)에서 α-Ni(rac-[14]-decane)2+의 화학평형 관계를 상온에서 분광광도법으로 연구하였다. ANT, MFA, DMSO, DMF, DMA일 때 평행상수 K1은 각각 31.0, 27.5, 21.3 15.9, 6.4이었으며 K2는 K1보다 적은 값이었다. α-Ni(rac-[14]-dacane)2+ + L ↔ [α-Ni(rac-[14]-decane)·L]2+ : K1[α-Ni(rac-[14]-decane)·L)2+ + L ↔ [α-Ni(rac-[14]-decane)·L2)2+ : K2.ACT에서 Ni(Ⅱ)-macrocycle 착이온의 d-d흡수에너지를 크게하는 거대고리 리간드일수록 착이온의 반파전위는 좀더 양의 값으로 이동하였다. Ni(rac-1[14]7-diene)2+, Ni(meso-1[14]7-diene)2+, Ni(1[14]4-diene)2+, α-Ni(rac-[14]-decane)2+, β-Ni(rac-[14]-decane)2+, Ni(meso-[14]-decane)2+ 착이온의 환원반파전위는 각각 -1.419, -1.431, -1.450, -1.473, -1.480 (V vs. SCE)이었다. 몇 가지 용매에서 Ni(meso-[14]-decane)2+ 이성질체의 d-d전이에너지(νmax, cm-1) 변화와 용매의 유전상수(ε/εo) 관계를 고찰하였으며 ε/εo가 클수록 νmax,(cm-1)는 증가하였다. The equilibria of chemical reaction between α-Ni(rac-[14]-decane)2+ and polar solvents(L; ANT, MFA, DMSO, DMF, and DMA) have been investigated by the spectrophotometric method at 25℃. (The equilibrium constants(K1) of) the first step in ANT, MFA, DMSO, DMF, and DMA were 31.0, 27.5, 21.3 15.9, and 6.4, respectively. The smallness of equilibrium constants (K2) of the second step compared with K1, was observed. α-Ni(rac-[14]-dacane)2+ + L ↔ [α-Ni(rac-[14]-decane)·L]2+ : K1[α-Ni(rac-[14]-decane)·L)2+ + L ↔ [α-Ni(rac-[14]-decane)·L2)2+ : K2. The relationship between d-d absorption energy and half-wave potential of complex ions at ACT was considered. Macrocyclic ligands increasing d-d transition energy caused half-wave potentials of Ni(Ⅱ)-macrocycle to be shifted more positively. The half-wave potentials for Ni(rac-1[14]7-diene)2+, Ni(meso-1[14]7-diene)2+, Ni(1[14]4-diene)2+, α-Ni(rac-[14]-decane)2+, β-Ni(rac-[14]-decane)2+, and Ni(meso-[14]-decane)2+ reductions were -1.419, -1.431, -1.450, -1.473, and -1.480 (V vs. SCE), respectively. The d-d transition energies (νmax, cm-1) of the Ni(meso-[14]-decane)2+ isomer were discussed with the dielectric constant (ε/εo) of the various solvents, νmax(cm-1) increased with increasing ε/εo. |
