The laser-induced fluorescence excitation spectrum of jet-cooled NiF has been studied in the range 435-570 nm. Eight electronic transitions, involving four high-lying Pi components and two lower states, the ground state X(2)Pi(3/2), and the low-lying state [0.25](2)Sigma, respectively, have been recorded. Two new Pi components are identified for the first time and their rotational constants are determined. The [20.4]Pi(3/2) component is assigned as the v'=1 level of the previously known [19.7](2)Pi(3/2) state. The [20.3]Pi(3/2) component may be linked to the component of an unreported quartet state. The previously reported [20.0](2)Pi(1/2) component is reassigned as a subcomponent of (2)Delta. Copyright 2001 Academic Press.

中文翻译：

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通过激光诱导荧光识别 NiF 的高位 Π 组分

已经在 435-570 nm 范围内研究了喷射冷却 NiF 的激光诱导荧光激发光谱。已经记录了八个电子跃迁，分别涉及四个高位 Pi 分量和两个低位态，即基态 X(2)Pi(3/2) 和低位态 [0.25](2)Sigma。首次确定了两个新的 Pi 分量并确定了它们的旋转常数。[20.4]Pi(3/2) 分量被指定为先前已知的 [19.7](2)Pi(3/2) 状态的 v'=1 级。[20.3]Pi(3/2)分量可以链接到未报告的四重态的分量。先前报告的 [20.0](2)Pi(1/2) 组件被重新分配为 (2)Delta 的子组件。版权所有 2001 学术出版社。