Derivation of Lanthanide Series Crystal Field Parameters From First Principles

Julie Jung , Md. Ashraful Islam (1, 2) , Vincent Pecoraro (3) , Talal Mallah (4) , Claude Berthon (5) , Hélène Bolvin (1, 2)

1 SEM - Systèmes étendus et magnétisme (LCPQ)
2 LCPQ - Laboratoire de Chimie et Physique Quantiques
3 Department of Chemistry, University of Michigan
4 ICMMO - Institut de Chimie Moléculaire et des Matériaux d'Orsay
5 DRCP - Département RadioChimie et Procédés

Two series of lanthanide complexes have been cho- sen to analyze trends in the magnetic properties and crystal field parameters (CFPs) along the se- ries: the highly symmetric LnZn 16 (picHA) 16 series with Ln = Tb, Dy, Ho, Er, Yb and picHA=picoline hydroxamic, and the [Ln(DPA)3 ](C3H5N2)3·3H2O series with DPA = 2,6-dipicolinic acid and Ln = Ce–Yb and with approximate three-fold symmetry. The first series presents a compressed coordination sphere of 8 oxygen atoms environment while in the 2nd series, the coordination sphere is formed by an elongated coordination sphere formed by six oxy- gen atoms. CFPs are deduced from ab initio cal- culations using two methods: the AILFT (Ab Ini- tio Ligand Field Theory) which determines the pa- rameters at the orbital level, and the ITO (Irre- ducible Technique Operator) decomposition which treats the problem at the many-electron level. It is shown that the CFPs are transferable from one derivative to the other, within a given series, as a first approximation. The sign of the 2nd order pa- rameter B02 differs in the two series reflecting the different environments. It is shown that the use of strength parameter S allows for an easy com- parison between complexes. Furthermore, in both series, the parameters are found to decrease in mag- nitude along the series and this decrease is imputed

Mots clés: ab initio calculations; crystal field theory; magnetic properties; lanthanides

Domaines: Chimie théorique et/ou physique; Chimie inorganique

Julie Jung, Md. Ashraful Islam, Vincent Pecoraro, Talal Mallah, Claude Berthon, et al.. Derivation of Lanthanide Series Crystal Field Parameters From First Principles. Chemistry - A European Journal, 2019, 25 (66), pp.15112-15122. ⟨10.1002/chem.201903141⟩. ⟨hal-02381772⟩