Institut für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany.
Chem Asian J. 2012 Jun;7(6):1261-95. doi: 10.1002/asia.201100776. Epub 2012 Mar 2.
We design a circularly polarized laser pulse in the infrared frequency and femtosecond time domains, for excitation of the OsH(4) molecule in its first excited pseudorotational state of the triply-degenerate bend. The OsH(4) molecule need not be pre-oriented. After excitation, the central nucleus Os carries out pseudorotation about the axis parallel to the direction of propagation of the laser pulse. This pseudorotation causes a strong electric ring current with a value I=1.53 e fs(-1). The mean value of the radius of the ring current is very small, R=0.0031 a(0), where a(0) is the Bohr radius. According to the Biot-Savart law (|B(R=0)| ~I/R)), this nuclear ring current induces the strongest magnetic field predicted so far in molecules, with a central peak absolute value |B(R=0)| =623 T. To monitor the effect, we propose an IR-pump-X-ray-probe versus an X-ray-probe-only experiment, at the K- and L-edges of X-ray ionization. The results are based on the general quantum theory of excitations of pseudorotations in tetrahedral molecules AB(4), driven by a circularly polarized laser pulse.
我们设计了一个在红外频率和飞秒时域内的圆偏振激光脉冲，用于激发三重简并弯曲的 OsH(4)分子的第一激发赝旋转态。OsH(4)分子不需要预先定向。激发后，中心核 Os 围绕与激光脉冲传播方向平行的轴进行赝旋转。这种赝旋转产生一个强的环形电流，其值为 I=1.53 e fs(-1)。环形电流的平均半径非常小，R=0.0031 a(0)，其中 a(0)是玻尔半径。根据毕奥-萨伐尔定律（|B(R=0)| ~I/R）），这个核环电流诱导出迄今为止在分子中预测到的最强磁场，中心峰值绝对值|B(R=0)| =623 T。为了监测这种效应，我们提出了一个 IR-泵-X 射线探测实验与仅 X 射线探测实验的对比，在 X 射线离化的 K 和 L 边缘。结果基于 AB(4)四面体分子的赝旋转激发的一般量子理论，由圆偏振激光脉冲驱动。
