Investigations of Infra-red Spectra ...Carnegie institution of Washington, 1906 |
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absorption bands Anhydrite Aschkinass bands at 1.5 brucite calcite cent Cleavage parallel Cleavage piece parallel coincide Colemanite complete opacity complex compounds DATOLITE emission energy feldspar film flame fluorite glass rod H₂SO Hagen and Rubens heat Heulandite HYDROTALCITE hydroxyl groups III-INFRA-RED infra-red instrument Investigations of Infra-red Kieserite large absorption band large band loop Massive maxima mellite melted metal method mica mirror molecule of water moon nitrate noticed observed obtained Orthoclase P₂O Pfund Phys plates of rock pleochroism Potassium present examination quartz quartz fiber radiation radical radiometer radiomicrometer rays reflection band reflection curve REFLECTION SPECTRA region rock salt Scolecite selective reflection selenite sensitiveness sharp shifted silicates silver small bands solid solution specimen spectrometer slit stibnite substance subtranslucent sugar suspension temperature thickness thin tion Transmission 40 30 Transmission 60 transparent visible spectrum water bands water of constitution water of crystallization willemite writer
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Pagina 101 - ... water, then the absorption spectra of minerals containing these two elements thus united should show the absorption bands of water superposed upon the absorption spectrum of the other constituents. On the other hand, minerals containing oxygen and hydrogen as water of constitution should not show the water bands, except hydroxyl groups, which should show a band at 3 /*. The results show that of about 30 minerals containing "Water of crystallization" there are no important exceptions to the rule...
Pagina 11 - ... spectroscopic data in two ways : (i) from consideration of intensities and ionization potentials of lines observed; (ii) from relative line intensities considering the processes of ionization, excitation, and recombination in detail. Because of a lack of data on...
Pagina 4 - The manner in which the water exists in the crystal is not understood. By some it is considered a part of the chemical molecule ; by others it is thought that the molecules of water exist in their entirety among the molecules which constitute the crystal.
Pagina 101 - The results show that of about 30 minerals containing "Water of crystallization" there are no important exceptions to the rule that they should show the bands of water. On the other hand the one important exception to the rule that minerals containing "water of constitution" should not show water bands is cane sugar.
Pagina 4 - On the other hand, the water which is given off only at a red or even a white heat can scarcely be present in the compound in the same manner as the water of crystallization, and is distinguished as •water of constitution.
Pagina 101 - On the other hand silicates do not have such definite bands, which would seem to indicate that the structure of the silicate radical is different in each mineral containing that element. The examination includes minerals of which the chemical constitution is in doubt; for example, talc and serpentine. The former is not supposed to contain hydroxyl groups while in the latter such groups are inferred. The present research supports these views in that the transmission curve of talc does not contain...
Pagina 16 - CENT 14 15« showing the permanence of the 4.55 p band. Beyond 6 /* the transparency increases and becomes 1.5 times as great as selenite at 6.9 p. The dehydrated section, which is an opaque white mass, was then moistened with water and allowed to stand over night to dry and set, just as in the case of plaster of Paris. The result is shown in curve...
Pagina 15 - ... and an enormous band at 4.55 /*, which will be shown later to be due to the SOt ion. Turning to the selenite curve, a, Fig. 2, it will be noticed that it is less transparent, for the same thickness, 0.65 mm, and that in its general trend it is similar to the curve for water. All of its absorption bands coincide with those of water, with the exception of the 4.75 p band, which is shifted to 4.6 p.
Pagina 5 - ... perplexing question makes use of the results of previous work in which it was shown by others as well as by the writer that certain groups of atoms have characteristic absorption bands. Hence, if the oxygen and the hydrogen which enter into the composition of certain minerals as " water of crystallization " are united as they are in a molecule of water then one would expect to find the absorption spectra of such minerals to be a composite of the bands of water, and of the bands caused by the...
Pagina 6 - To sum up, in the present investigation the criterion for distinguishing water of crystallization from water of constitution is the presence of absorption bands at 1.5, 2, 3, 4.75, and 6/*, which is the location of the absorption bands of water.