[260] Sitzungsber. kaiserl. Akad. Wiss. Wien, 1903, 112, 1037.

[261] Amer. Chem. J. 1898, 20, 345.

[262] Zeitsch. anorg. Chem. 1898, 17, 310.

[263] Zeitsch. anorg. Chem. 1906, 50, 249.

Brauner’s earlier work,[264] carried out in 1898, gave the value 140·95. In 1901 this author[265] carried out an extensive research on the atomic weight of praseodymium, employing four different methods with spectroscopically pure material; the mean value of his very concordant results was 140·97, almost the value he obtained in 1901. A further investigation into the value of this constant appears desirable.

[264] Proc. Chem. Soc. 1898, 14, 70.

[265] Ibid. 1901, 17, 65; see also Abegg, III, i. 263.

Detection.

—The maxima of the absorption bands are given by Rech[266] as follows:

Yellow596·4 and 588·2, weak.
Blue481·3 very intense.
468·3 coincident with a neodymium band.
Violet444·2