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In the review of the crystallographic properties of platinum by the present author (1), the high-temperature data were represented by expressions derived from precision dilatometric thermal expansion measurements (Equations (i) and (ii)). Above 1000 K temperature, not only did length change measurements derived from lattice parameter measurements fail to agree with one another, they also showed marked scatter around the dilatometric results. The length change measurements were therefore unsuitable for calculating the lattice parameter thermal expansion. This problem was addressed by correcting the dilatometric data for thermal vacancy effects (Equations (iii) and (iv)), based on the consistent set of thermal vacancy parameters given in Table I and explained in the original review (1).

High Temperature Dilatometric Thermal Expansion (293.15–2041.3 K)

  α* = 7.08788 × 10⁻⁶ + 1.04970 × 10⁻⁸ T

    − 2.00846 × 10⁻¹¹T² + 2.28200 × 10⁻¹⁴T³

    − 1.18453 × 10⁻¹⁷T⁴ + 2.37348 × 10⁻²¹T⁵ K⁻¹    (i)

  δL/L_{293.15 K} = 7.08788 × 10⁻⁶ + 5.24850 × 10⁻⁹ T² − 6.69487 × 10⁻¹² T³

    + 5.70500 × 10⁻¹⁵ T⁴ − 2.36906 × 10⁻¹⁸ T⁵

    + 3.95580× 10⁻²²T⁶ − 2.39745 × 10⁻³        (ii)

Thermal Vacancy Corrections (1300–2041.3 K)

  α*_(lattice) = α*_{(dilatometric)} − (5841/T²) e^{(1.32 −17523/T)} K⁻¹   (iii)

  δa/a_{293.15 K} = δL/L_{293.15 K} − (1/3) e^{(1.32 − 17532/T)}      (iv)

Note: in Equation (x) of Ref. (1), to which Equation (iv) corresponds, the second δ was incorrectly given as d.

On reflection, this procedure is cumbersome and might be considered unsatisfactory. It has therefore been replaced here by Equations (v) and (vi) which are based on a combination of Equations (i) and (iii), and which represent the lattice parameter thermal expansion from 293.15 K to the melting point at 2041.3 K. Equation (v) agrees with a combination of Equations (i) and (iii) to within 4 × 10⁻⁹ K⁻¹ and to within ± 2 × 10⁻⁹ K⁻¹ overall, well within the accuracy of Equation (i) of ± 2 × 10⁻⁸ K⁻¹.

In Equations (i), (iii) and (v), α* is the thermal expansion coefficient relative to 293.15 K.

High Temperature Lattice Thermal Expansion (293.15–2041.3 K)

  α* = 7.03139 × 10⁻⁶ + 1.08937 × 10 ⁻⁸ T

    − 2.10071 × 10⁻¹¹T² + 2.36623 × 10⁻¹⁴ T³

    − 1.20728 × 10⁻¹⁷T⁴ + 2.34219 × 10⁻²¹T⁵ K⁻¹    (v)

  δa/a_{293.15 K} = 7.03139 × 10⁻⁶ T + 5.44686 × 10⁻⁹T² − 7.00236 × 10⁻¹² T³

    + 5.91557 × 10⁻¹⁵ T⁴ − 2.41456 × 10⁻¹⁸ T⁵

    + 3.90366× 10⁻²²T⁶ − 2.39164 × 10⁻³       (vi)