REST-LTS .\SI)DIHCUGSIOS
-1cwrnp:irison of thc diffraction p:itt erns of indium hydroxides ;1and I3 proved them t o Ijr alike in el-c'ry tlet8ail. 130th kinds ~ l w \ \a- simple pattern resembling the lincl systcm given b y culiic mat crials.
.IBSORPTIOS SPECTRA O F -431130 ACIDS I S D COXPLEXES
BG1
of molecules of In(OH), per unit cell of lattice constant i.90 -1.n-ould be eight. The values agree with those reported previously by W.0. Milligan.1 Table 1 compoares observed and calculated interplanar distances, on the basis of aa = 7.90 A . and eight molecules per unit cell. SUnfVARY
X-ray diffraction data indicate that the yellou compound precipitated upon the addition of chromate to indium chloride has a crystalline structure identical x i t h that of indium hydroxide, and furnish further er-idence for the fact that 110 indium chromate is precipitated in this reaction. The cubic crystal structure of In(OHj3has a lattice constant of 7.90 i 0.04 -1. The appreciation of t8heauthor is due to Professor IT-. F. Ehret and Harry TYiener for their constant interest, and assist,ance and t,o Professor I. Fanlachen for some valuable discussions. 1: E FER E S C E S (1 I ~ I I L I , I ( ; .JV. ~ ~0. . : 1'iil)cr S o . 41 j i i abstracts of papers presciitrcl before t h e Ilirision of Physical alii1 Inorganic Cheiiiistry a t t h e 96th l i r e t i n g of t h e hniericaii C'hciiiical Societ!.. n.hich was held in 1Iiln-aukee, \Viseonsin, SeptriiihPr 5-9, 1938. ( 2 ) ~IILLIC;.II-, W.O . , ASII WEISER,H. B . : Trans. Faraday 8oc. 32, 373 (1936). (31 ~ I I I . I , I G A\I7. S > 0 . ..*si)JVILSLR. H. B . : J. Am. ChPin. doc. 59, 1670 (1937). ( 4 1 .\IOELLDR. TH... k S D k H S I Z I . I < l h ~ [ > . : ,J. Phys. Colloid ('hrin. 61, 771 (1947). ( 5 ) PAI.\J..I.: J. -4111, Chein. Yoc. 69, 224 (1947). 1 The author is indebted t o Dr. Milligan for c ~ l l i i i gher a t t e n t i o n t o this unpu1)li~liril paper.
I h e c t optical evidence of the dipolar nature of amino acids was furnished first by Edsall (3) in his studies of the Raman spectra of t'hese subst,ances. Raman frequencies of the carbosyl group of the amino acids definitely coincided with those observed for the a l l d i salts of aliphatic acids rather than with the values obtained with the non-ionized acids. -1dditional optical evidence of the dipolar 1 .ibstractcd f r o m a p o r t i o n of t h e tlicsis of D. 31. G r u c n . \\-liicli was prcLseritcd t o t h e F a c u l t y of thr Graduate? S~.lio01of S o r t h w c s t c r n I-nivcrsitJ- i i i partial fulfillnieiit of the requirenirnts for t h c 11,s.t l ( ~ g r c clIarcli. ~. 1947.
