EPR OF SOME VERDAZYL FREE RADICALS LOW DIMENSIONAL BEHAVIOR

Verdazyl自由基是一类具有吸引力的化合物， 有机/分子铁磁性质。 先前的研究 显示了单线EPR谱的线宽， 多晶Verdazyl样品随分子结构而变化。 在不同温度下的EPR线宽数据与磁性相关 磁化率揭示了铁磁相变在低 温度。 在目前的工作中，我们研究的角度变化的EPR 线宽的一些新类型的verdazyl自由基可用在一个 晶体形式。 观察到的线宽有一个“W形”的角度依赖性 这是低维（1-或2-D）自旋系统特征。 线宽角依赖性被用来分离长期和 非长期贡献的EPR线型。 EPR可以揭示 低维的自旋系统，即使在室温下，而 需要在宽温度范围内的磁化率数据 为指定自旋自旋的特定模型提供基础， 系统中的相互作用。

Verdazyl free radicals are a family of compounds with attractive organic/molecular ferromagnetic properties. Previous studies have shown that the linewidth of a single line EPR spectrum from polycrystalline verdazyl samples varies with themolecular structure. EPR linewidth data at various temperatures correlate with magnetic susceptibility revealing a ferromagnetic phase transition at low temperatures. In the present work we examine angular variation of EPR linewidth of some novel types of verdazyl radicals available in a crystal form. Observed linewidths have a "W-shape" angular dependence that is characteristic for low-dimensional (1- or 2-D) spin systems. Linewidth angular dependence was used to separate secular and nonsecular contributions to the EPR lineshape. EPR can reveal the low-dimensionality of the spin system even at room temperature, while magnetic susceptibility data in a wide temperature range are required to provide a basis for assigning a certain model for the spin-sp in interactions in the system.