A series of novel dibenzoylmethanatoboron difluoride (DBMBF₂) and methoxy-substituted DBMBF₂ dyads linked via flexible dimethylsiloxane linkers of variable length were synthesized and characterized. Both monomer and excimer (trough intramolecular excimer formation) emissions are observed for the dyads in dilute dichloromethane solutions at room temperature. The excimers contribution into the total fluorescence spectrum decreases with increasing siloxane linker length. The parallel-sandwich conformation of intramolecular pre-excimers formed by two terminal DBMBF₂ moieties is confirmed by DFT-based calculations.

中文翻译：

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柔性硅氧烷连接基连接的新型二苯甲酰甲基氨基硼酸二氟二元化合物的合成与性能

合成并表征了通过可变长度的柔性二甲基硅氧烷接头连接的一系列新颖的二苯甲酰甲基氨基硼酸二氟化物（DBMBF ₂）和甲氧基取代的DBMBF _2二联体。在室温下，在稀释的二氯甲烷溶液中观察到二元组的单体和准分子（低分子内准分子的形成）发射。准分子对总荧光光谱的贡献随着硅氧烷接头长度的增加而降低。通过基于DFT的计算证实了由两个末端DBMBF ₂部分形成的分子内准分子的平行夹心构象。