Pressure dependence of zero-field splittings in organic triplets. III: Vibronic systems
Pressure dependence of zero-field splittings in organic triplets. III: Vibronic systems
复制标题
有机三重态中零场分裂的压力依赖性。
DOI：
10.1063/1.462701
复制
发表时间：
1992
影响因子：
4.4
通讯作者：
I. Chan
中科院分区：
文献类型：
--
作者：
J. Baber;I. Chan
We report optically detected magnetic resonance (ODMR) experiments at pressures up to 40 kbar for p‐benzoquinone (BQ) in dibromobenzene (DBB) and for a deep x‐trap in a BQ‐d4 neat crystal. It is known from previous works that the phosphorescent triplet state (3B1g) of these systems is vibronically coupled to a nearby 3Au state, such that the former exhibits a double‐minimum potential well. The zero‐field splitting (ZFS) parameter D of both systems changes by several gigahertz over our pressure range. The greatest slope occurs at zero pressure, and the rate of change slows down exponentially at higher pressure. In addition, we observed a phase transition in BQ‐d4 crystals at 6 kbar, which causes a huge step‐discontinuity in both D and E. In contrast to the enormous change in D, the E‐value is not sensitive to pressure except for the step‐change during the phase transition. Triplet state kinetics and phosphorescence spectra are used to establish the existence of an in‐plane distortion at least in the high‐p...
