Utilizing Relativistic Effective Core Potentials for Accurate Calculations of Molecular Polarizabilities on Transition Metal Compounds

Abstract

The requirements necessary to extend an ECP basis set for the calculation of electric and linear optical properties to the transition metals are studied. Previously an augmentation of the SBK basis set for 39 elements with s and p electron only valences (H-Rn, excluding Ga, In, and Tl) [J. Comput. Chem., 2005, 26, 1464-1471] was presented. In this work, electric dipole moments, polarizabilities, and anisotropies of selected metal hydrides, sulfides, and bromides, cisplatin, and the Fe, Ru, and Os metallocene derivatives along with many other systems are calculated and discussed. ECP calculations of molecules containing 3d and 4d metal centers among main group atoms have good agreement, often within 1-2% of the all-electron result at the time-dependent Hartree-Fock (TDHF)/Sadlej level of theory. Molecules with a 5d metal center have a large difference from and are more accurate than the all-electron results due to the inclusion of relativistic effects in the ECPs. The polarizability as calculated with and without ECPs of metallic clusters and surfaces is increasingly different as atomic number increases, again due to a lack of relativistic effects in the all-electron calculations. The augmented ECP calculations are consistent with relativistic all-electron results, while the Sadlej calculations are consistent with other nonrelativistic results. Both relativistic and basis set effects are less noticeable when the metal is in a formally positive state.

Ferrocene Acidity and C–H Bond Dissociation Energy via Experiment and Theory

“…Likewise, water was found to protonate the conjugate base of ferrocene, but weaker acids did not. These bracketing results, summarized in Table , enable us to assign Δ H ° acid = 391.5 ± 1.3 kcal mol –1 for the acidity of ferrocene. − …”

Highly Birefringent Materials Designed Using Coordination Polymer Synthetic Methodology

“…However, long‐term exposure of 2 to light photodegraded the polymer, thus indicating that [Ag(CN) 2 ] − incorporation is actually detrimental. Although calculations for silver show a higher static polarizability than for gold, additional calculations on AgBr and AuBr suggest that the polarizability anisotropy is larger for AuBr;52 the observation that there is no difference in the optical anisotropy between 1 and 2 suggests that the optical anisotropies of gold and silver dicyanide are quite similar. That said, the use of the highly structurally anisotropic linear cyanometalates and their alignment in the crystal is vital to forming birefringent materials, as more commonly utilized hexacyanometalates would have isotropic polarizabilities 30…”

The Spectroscopic and Conductive Properties of Ru(II) Complexes with Potential Anticancer Properties

“…This functional has been reported to improve the accuracy of excitation energies and charge transfer bands in metal complexes both in gas phase and in solution [68]. Also, the ECP basis set has been pointed out as a viable method for accurate calculations of transition metal polarizabilities [69]. All of the computed properties were done using Becke's three-parameter exchange [70] and Lee-Yang-Parr's correlation nonlocal functional which is usually denoted by B3LYP, combined with different combination of basis set.…”