The introduction of heavy atoms into conjugated molecules often induces a redshift in the emission spectra. Conversely, we report here a blueshifting effect in the absorption and emission bands of a conjugated organic dye by employing a heavier atom from the same element group. Boron complexes having oxygen‐ and sulfur‐bridged structures in the ligand moiety were synthesized, and their optical properties were compared. Significant optical bands in the absorption and luminescence spectra of the sulfur‐bridged complex were observed in a shorter wavelength region than those of the oxygen‐bridged complex. Theoretical calculations suggest that replacement of the bridging atom by a heavier one should reduce molecular planarity because of the larger atom size. As a result, the degree of electronic conjugation decreases, and this is followed by a blueshift in the optical bands. Finally, a blue‐emissive crystal is demonstrated.

中文翻译：

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利用相同元素组的重原子设计短波长发光的共轭分子

将重原子引入共轭分子中通常会导致发射光谱发生红移。相反，我们在这里报告了通过使用来自相同元素组的较重原子在共轭有机染料的吸收带和发射带中的蓝移效应。合成了在配体部分具有氧桥和硫桥结构的硼配合物，并比较了它们的光学性质。在比氧桥联络合物短的波长范围内，观察到硫桥联络合物的吸收光谱和发光光谱中有明显的光带。理论计算表明，由于原子尺寸较大，用较重的原子取代桥连原子应降低分子的平面度。结果，电子共轭度降低，随之而来的是光学波段的蓝移。最后，演示了发射蓝色的晶体。