10.1021/jp7115966.s002 Ling Jiang Ling Jiang Xi Jin Xi Jin Mingfei Zhou Mingfei Zhou Qiang Xu Qiang Xu CO Activation on the Late Lanthanide Dimers:  Matrix Infrared Spectra of the Ln<sub>2</sub>[η<sup>2</sup>(μ<sub>2</sub>-C, O)]<i><sub>x</sub></i> (Ln = Tb, Dy, Ho, Er, Lu; <i>x</i> = 1, 2) Molecules American Chemical Society 2008 cm Ln Lu Tb lanthanide atoms Yb carbon monoxide molecules Ho Dy theory calculations CO moieties sample annealing dilanthanide carbonyls range Tm CO Activation Er 2008-04-24 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/CO_Activation_on_the_Late_Lanthanide_Dimers_Matrix_Infrared_Spectra_of_the_Ln_sub_2_sub_sup_2_sup_sub_2_sub_C_O_i_sub_x_sub_i_Ln_Tb_Dy_Ho_Er_Lu_i_x_i_1_2_Molecules/2942992 Reactions of laser-ablated late lanthanide atoms (Tb, Dy, Ho, Er, Tm, Yb, and Lu) with dilute carbon monoxide molecules in solid argon have been investigated using matrix-isolation infrared spectroscopy. The Ln<sub>2</sub>[η<sup>2</sup>(μ<sub>2</sub>-C, O)]<i><sub>x</sub></i> (Ln = Tb, Dy, Ho, Er, Lu; <i>x</i> = 1, 2) molecules are observed upon sample annealing, whereas no product is observed for Tm and Yb. The C−O stretching frequencies in these dilanthanide carbonyls range from 1100 to 1300 cm<sup>-1</sup>, far below the value of free CO in the gas phase (2143.5 cm<sup>-1</sup>), implying that the C−O bonds are highly activated. Density functional theory calculations have been performed on these products. These Ln<sub>2</sub>[η<sup>2</sup>(μ<sub>2</sub>-C, O)]<i><sub>x</sub></i> molecules are predicted to have planar structures, which carry asymmetrically bridging CO moieties that are tilted to the side.