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Lawrence Berkeley National Laboratory Recent Work Lawrence Berkeley National Laboratory Recent Work Title Chemistry Division Quarterly Report for June, July and Aug. 1949 Permalink https://escholarship.org/uc/item/1sj33680 Author Lawrence Berkeley National Laboratory Publication Date 1949-09-27 eScholarship.org Powered by the California Digital Library University of California UCRL 460 Cy. 68/A UNIVERSITY OF CALIFORNIA '', ' \ .... TWO-WEEK LOAN COPY This is a library Circulating Copy which may be borrowed for two weet~s. For a personal retention copy, call Tech. Info. Diuision, Ext. 5545 .,- BERKELEY, CALIFORNIA DISCLAIMER This document was prepared as an account of work sponsored by the United States Government. While this document is believed to contain correct information, neither the United States Government nor any agency thereof, nor the Regents of the University of California, nor any of their employees, makes any warranty, express or implied, or assumes any legal responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by its trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof, or the Regents of the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof or the Regents of the University of California. UNIVERSITY OF CALIFORNIA Radiation Laboratory Gover Sheet INDEX NO. Do not remove itc ,e,L «'tJ This document contains __tiS pages This is copy k.. of ....J.i- Series ..L2 Issued to _____.:::~~:..:::"';:z...=-A2...-·~M.::::·~~!::::Z~ ;.:.;J·:.._ ____ Classification Each person who receives this document must sign the cover sheet in the space below Route to Noted by Date Route to Noted by Date .~ ~ ~~l.s-7 J . ' /j UCRL 460 Chemistry=Transuranie Elements f0EClAS-S~FIED .. UNIVERSITY Ol!., CALIFORNIA Radiation Laboratory r Contra~t Noo W=7405=eng=48 ClASSIF1CATrON CANCEllED BY AUTHCRITY OF _ • :JJ2J.;dljj';_~c;;o~ I; 3 SIGNATURe; OF TH<: ·• 3- 3/.-~ PEREON MAKING TH5 DA;Tf' • CHANGE CHEW~STRY DIVISION Q.UARTF.RLY REPORT Junev July and August 1949 ,.' September 27 9 1949 CAUTION c' '·· Berkeleyv California -2- STANDARD DISTRIBUTION / Series A Copy Numbers Argonne National Laboratory 1=10 Atomic Energy Commission, Washington 11=12 Brookhaven National Laboratory 13=16 Carb1.de and. Carbon Chemicals Corporation (K-25 Plant) 17=20 General Electric Company 9 Richland 21=26 Hanford Operations Office 27 Iowa State College 28 Kellex Corporation 29=30 Knolls Atomic Power Laboratory 31=34 Los Alamos 35-37 Naval Radiological Defense Laboratory 38 NEP.A. Project 39 New York Operations Office 40-41 Oak Ridge National Laboratory 42-49 Patent Branchv Washington 50 Technical Information Branch 9 ORE 51~65 UCLA Medical Research Laboratory (Warren) 66 University of California Radiation Laboratory 67=69 University of Rochester 70=71 INFOR~ION DIVISION Radiation Laboratory Univo of California Berkeley9 California TABLE OF CONTENTS Page I Q.U.ARTERLY PROGRESS REPORTo Project 48 Ao Chemistry of the Rare Earths and Actinide Elements .. Chemistry of Neodymium 9 Samarium and Gadolinium 4 The Vapor Phase Hydrolysis of Lanthan Trichloride 6 Chemistry of Vitamin B12 8 Bo Nuclear Properties and Transformations Bombardment of Copper with Protons 9 Alpha Particle Decay in Rare· Earth Isotopes 10 Neutron Deficient Rare Earth Isotopes 12 Bismuth Isotopesi Masses 198-203 13 Bi205 9 p 0 203 9 Pb 98 9 Rb81 and Kr81 15 Search for Heavy Polonium Isotope 16 Low Mass Isotopes of Astatine 18 · New Isotopes of Francium 19 Excitation Function Work on Thorium 20 Fission Product Yield Distribution from Bombardment of Natural Uranium with 350 Mev Protons 21 a Plutonium and Neptunium Isotopes 23 Beta=Spectrometer 24 Mass Spectrograph 26 Spontaneous Fission 27 Co Chemistry of Astatine and the Preparation of Certain Compounds 28 Do Bio-Organic Chemistry Group Synthetic and Experimental Chemistry 29 Biological Chemistry 38 Photosynthesis Chemistry 42 II QUARTERLY PROGRESS REPORT. Project 48B Ao Metals and High Temperature Thermodynamics 49 Bo Basic Chemistry9 including Metal Chelates 51 ·• Co Ore Reduction 52 Do Engineering Development of Plutonimn Separation 53 DECLASS~FrED UCRL 460 I Q,U.ARTERLY PROGRESS REPORT o . PROJECT 48 + Ao Chemistry of the Rare Earths and Actinide Eleme<nt:s ' Io Perlmanv Bo B. Cunningham and Co=worker:s Chemistry of Neodymium; Samarium and Gadolinium James Co Wallman and Bo B o Cunningham Chemistry of Neodymium. An improved balance for measuring magnetic sus~eptibilities has been con­ st~l~tedo A permanent magnet is placed in an upright position to give a vertical · displacement to the sample; this deflection is measured by a quartz fiber torsion balance of the Kirk=Craig=Gulberg typeo The balance has a sensibility of approxi= mately OoOOl m.icrogramso With the aiin of elucidating the composition of the sodium vapor reaction products of rare·earth trifluorides~ the magnetic susceptibility of several ©ompounds has been determined using this apparatuso Calibration of the balance is based upon observations using Mohrus salt 9 Fe(NJ4) 2{so4)2 o6H20 9 as the standardo The value of the effective moment of Mohrus salt used for cal~ulating the specific sus~eptibility is 5o25 Bohr magnetons~ X = 29o6 x 10=60 Three preparations of NdF3 gave specific susceptibilities of 28o94 0 30o84 eAd 29o39 (11nit of X is 1 x 10=6 ~gs electromagnetic units)o Seven sodium reduc= tions of these trifluorides were made of which four resulted in blaek=eoated pellets with pink.coreso X=ray analysis indicated the presence of principally NdF3 with only pa.r·tial reaction to give the fluorite=patterned product presumed to be NdOF or NdF2o Magnetic susceptibility measurements indicated no reduction~ ·X wa.lues of 29o66v 30'o02v 29o23 and 30o25 were obtainedo Reduction of NdF3 to NdF 2 B>hould decrease the susceptibility by about 28 percento Coprecipitation of .f> CaF2 and NdF3 resulted in a product of susceptibility about 1/3 that of NdF3 and reaction with sodium metal caused the susceptibility to increasev· probably due to traces of iron impurity in the sampleo , Chemistry of 'Sa.m.ari:umo ., Reduction to SmF2 is ,to be expected in the case ot SmF3 and magnetic measure­ ments for two runs indicate reductions of 35 and 60 percent completeness~ X of value 6o23 increasing to l2o32 and 19o99. Reaction of copreci.pitat;ed CaF2oSmF3 with Na resulted in a change of susceptibility indicating 100 percent formation of .,... samarium difluoride a Chemistry of Gadoliniumo The susceptibility of GdF 3 was measured as 132o6 and 127o0o Treatment of the ..... GdF:; with Na vapor at ,1125°0 gave products with susceptibilities of 126o8 9 139o8 9 0 and l3lo5o As in the.case of NdF3D no reaction product gave a sus~eptibility indicating even partial reduction to the difluoride and no product was obtained with UCRL 460 a pure fluorite x~ray patterno One reaction did result in formation of GdF3 with hexagonal lattice symmetry and of UCl3 structure type 9 as opposed to the hexagonal ! LaF3 type usually formado Contrary to results obtained earlier (see UCRL=.311 and UCRL=382) the magneti© measurements on the rare earths indicate that the trifluoride=sodium metal rea@tion produ~t is probably not a difluoride; however 9 none of the products tested exhibited a pure fluorite structure~ an indeterminate amount of trifluoride is always presento Further work to obtain a pure fluorite=patterned product is in progresso Chemii~Sal analysis of the reaction products would also indicate the eomposi= tir8ln and mu©h effClrt has been devoted to developing a method of analysing for fluoride contento There are no ~emimicro gravimetric or volumetric analysis yields results of the accuracy requiredo A gravimetric analysis for the rare ear·th ion has been d~velbped and appears to be the most feasible method ot· chemi©al an.alysiso '1, UCRL 460 The Vapor Phase Hydrolysis of Lanthanum Trichloride A o Broido and Bo Bo Cunningham Notably absent from standard ~ompilation of thermochemical data (such as those of., Bichowski and Rossini P or those of Brewers Bromley 9 Gilles and Lofgren) are data pertaining to the rare earth oxyhalides.; Existing methods for the prepara­ tion of these ©ompounds are based on purely empirical procedureso The oxyhalides nevertheless constitute an important class of compoundso The ease of formation of the o::x:yehlorj,des and o:x:ybromides 9 for e:x:ample 9 is a major source of difficulty in the attempted preparation of pure samples of the corresponding trihalideso The presen©e of oxyhalide. impurities not only introduces an element of uncertainty in all obsel';'il'ations on the pr10lperties of the trihalide samplev but may have a ·notably deleter:'l.ous ef'fe©t on some of the chemical react ions of the trihalide = the reduc­ tion to metal by metallic reductantsv for exampleo We have therefore undertaken a systemati© investigation of the free energy of the reaction by measurement of the equilibrium constants at various temperatureso In the equation R symbolizes a rare earth cationo It is intended that this investigation shall cover not only the available rare earthsv but several of the actinide elements as wello The ini.tial measurements 9 some of which have been reported before 9 have
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