Anharmonic force fields of perchloric acid, HClO${}_4$, and perchloric anhydride, Cl${}_2$O${}_7$. An extreme case of inner polarization

Abstract

DFT (density functional theory) anharmonic force fields with basis sets near the Kohn-Sham limit have been obtained for perchloric acid, HClO${}_4$, and perchloric anhydride, Cl${}_2$O${}_7$. Calculated fundamental frequencies are in very good agreement with available experimental data. Some reassignments in the vibrational spectra of Cl${}_2$O${}_7$ are proposed based on our calculations. HClO${}_4$ and Cl${}_2$O${}_7$ are particularly severe examples of the `inner polarization' phenomenon. The polarization consistent basis sets pc-1 and pc-2 (as well as their augmented counterparts) should be supplemented with two (preferably three) and one (preferably two) high-exponent $d$ functions, respectively, on second-row atoms. Complete anharmonic force fields are available as electronic supporting information.

J. Mol. Struct., in press (special issue); Electronic Supporting Information at http://theochem.weizmann.ac.il/web/papers/Cl2O7.html

References in corpus (4)

• The Role of the Basis Set: Assessing Density Functional Theory
• Vibrational Spectra of the Azabenzenes Revisited: Anharmonic Force Fields
• Assessment of Various Density Functionals and Basis Sets for the Calculation of Molecular Anharmonic Force Fields
• Anharmonic force fields and thermodynamic functions using density functional theory

Cited by in corpus (2)

• Heats of formation of perchloric acid, HClO${}_4$, and perchloric anhydride, Cl${}_2$O${}_7$. Probing the limits of W1 and W2 theory
• Electron Correlation: Nature's Weird and Wonderful Chemical Glue