An Ab Initio Study of Boric Acid,
Borate, and their Interconversion
Cory C. Pye
Abstract The chemistry of boric acid and monomeric borates is reviewed. Following a discussion of the crystal structures and nuclear magnetic resonance
studies, ab initio results are presented of molecular ortho- and metaboric acid,
(tetrahydroxo)borate, and the hydrates of orthoboric acid and borate. The structures
and vibrational frequencies are compared with experiment. Attempts to study their
interconversion lead us to a discussion of oxodihydroxoborate (the conjugate base
of boric acid), and of the hydroxide-boric acid complex. It is hypothesized that the
conversion of boric acid into borate proceeds via the oxodihydroxoborate intermediate. Finally, the calculated structures of hydroxodioxo- and trioxoborate are
compared with experiment.
Keywords Boric acid ⋅ Borate ⋅ Ab initio
1 Introduction
The nature of boron(III) in aqueous solution has been of longstanding interest to
chemists as numerous hydroxooxoborates can exist as anions in metal ion salts [1].
The isotope
10 B has important applications in nuclear science because of its large
thermal neutron absorption cross section, and the separation of
10
B (natural
abundance 19.58%) from the remaining
11 B (natural abundance 80.42%) is an
important technological problem requiring knowledge of the reduced partition
function ratio for isotope exchange [2–4]. Many borate minerals exist in nature and
the pure compounds can sometimes be prepared in the laboratory. The boron
Electronic supplementary material The online version of this chapter (https://doi.org/10.1007/
978-3-319-74582-4_8) contains supplementary material, which is available to authorized users.
C. C. Pye ( ✉ )
Department of Chemistry, Saint Mary’s University, Halifax, NS B3H 3C3, Canada
e-mail: cory.pye@smu.ca
© Springer International Publishing AG, part of Springer Nature 2018
Y. A. Wang et al. (eds.), Concepts, Methods and Applications of Quantum Systems
in Chemistry and Physics, Progress in Theoretical Chemistry and Physics 31,
https://doi.org/10.1007/978-3-319-74582-4_8
143
Borate, and their Interconversion
Cory C. Pye
Abstract The chemistry of boric acid and monomeric borates is reviewed. Following a discussion of the crystal structures and nuclear magnetic resonance
studies, ab initio results are presented of molecular ortho- and metaboric acid,
(tetrahydroxo)borate, and the hydrates of orthoboric acid and borate. The structures
and vibrational frequencies are compared with experiment. Attempts to study their
interconversion lead us to a discussion of oxodihydroxoborate (the conjugate base
of boric acid), and of the hydroxide-boric acid complex. It is hypothesized that the
conversion of boric acid into borate proceeds via the oxodihydroxoborate intermediate. Finally, the calculated structures of hydroxodioxo- and trioxoborate are
compared with experiment.
Keywords Boric acid ⋅ Borate ⋅ Ab initio
1 Introduction
The nature of boron(III) in aqueous solution has been of longstanding interest to
chemists as numerous hydroxooxoborates can exist as anions in metal ion salts [1].
The isotope
10 B has important applications in nuclear science because of its large
thermal neutron absorption cross section, and the separation of
10
B (natural
abundance 19.58%) from the remaining
11 B (natural abundance 80.42%) is an
important technological problem requiring knowledge of the reduced partition
function ratio for isotope exchange [2–4]. Many borate minerals exist in nature and
the pure compounds can sometimes be prepared in the laboratory. The boron
Electronic supplementary material The online version of this chapter (https://doi.org/10.1007/
978-3-319-74582-4_8) contains supplementary material, which is available to authorized users.
C. C. Pye ( ✉ )
Department of Chemistry, Saint Mary’s University, Halifax, NS B3H 3C3, Canada
e-mail: cory.pye@smu.ca
© Springer International Publishing AG, part of Springer Nature 2018
Y. A. Wang et al. (eds.), Concepts, Methods and Applications of Quantum Systems
in Chemistry and Physics, Progress in Theoretical Chemistry and Physics 31,
https://doi.org/10.1007/978-3-319-74582-4_8
143