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Nucleation of neutral iodine particles has recently been found to involve both iodic acid (HIO3) and iodous acid (HIO2). However, the precise role of HIO2in iodine oxoacid nucleation remains unclear. Herein, we probe such a role by investigating the cluster formation mechanisms and kinetics of (HIO3)m(HIO2)n(m = 0-4, n = 0-4) clusters with quantum chemical calculations and atmospheric cluster dynamics modeling. When compared with HIO3, we find that HIO2binds more strongly with HIO3and also more strongly with HIO2. After accounting for ambient vapor concentrations, the fastest nucleation rate is predicted for mixed HIO3-HIO2clusters rather than for pure HIO3or HIO2ones. Our calculations reveal that the strong binding results from HIO2exhibiting a base behavior (accepting a proton from HIO3) and forming stronger halogen bonds. Moreover, the binding energies of (HIO3)m(HIO2)nclusters show a far more tolerant choice of growth paths when compared with the strict stoichiometry required for sulfuric acid-base nucleation. Our predicted cluster formation rates and dimer concentrations are acceptably consistent with those measured by the Cosmic Leaving Outdoor Droplets (CLOUD) experiment. This study suggests that HIO2could facilitate the nucleation of other acids beyond HIO3in regions where base vapors such as ammonia or amines are scarce. publishedVersion

f-element-bearing iodate compounds are a large family mostly synthesized by hydrothermal reactions starting with actinide/lanthanide ions and iodic acid or iodate salt. In this work, we introduce melting periodic acid flux as a new reaction medium and provide a safe way for single-crystal growth of a series of new f-element iodate compounds including UO2(IO3)2·H2O (1), UO2(IO3)2(H2O)·HIO3 (2), α-Th(IO3)2(NO3)(OH) (3), β-Th(IO3)2(NO3)(OH) (4), and (H3O)9Nd9(IO3)36·3HIO3 (5). The structures of these compounds deviate from those afforded from hydrothermal reactions. Specifically, compounds 1 and 2 exhibit pillared structures consisting of uranyl pentagonal bipyramids and iodate trigonal pyramids. Compounds 3 and 4 represent two new thorium iodate compounds that are constructed from subunits of thorium dimers. Compound 5 exhibits a flower-shaped trivalent lanthanide iodate structure with HIO3 molecules and H3O+ cations filled in the channels. The aliovalent replacement of f elements in 5 is available from a h...

Iodic acid (HIO3) was exploited as the effective source to build an artificial solid-electrolyte interphase (SEI) on the surface of Li anode. On one hand, HIO3 is a weak solid-state acid and can be easily handled to remove most ion-insulating residues like Li2CO3 and/or LiOH from the pristine Li surface; on the other hand, both the products of LiI and LiIO3 resulted from the chemical reactions between Li metal and HIO3 are reported to be the ion-conductive components. As a result, the lower voltage polarization and impedance, longer cycling lifetime and higher Coulombic efficiency have been successfully achieved in the HIO3-treated Li–Li and Li–Cu cells. By further using the HIO3-treated Li anode into practical Li–S batteries, the impressive results also have been obtained, with average discharge capacities of 719 mAh g–1 for 200 cycles (0.2 C) and 506 mAh g–1 for 500 cycles (0.5 C), which were better than the Li–S batteries using the pristine Li anode (552 and 401 mAh g–1, respectively) under the same co...

The iodine-arsenous acid (Roebuck), iodide-iodate (Dushman), and iodate-arsenous acid reactions have been studied simultaneously by a stopped-flow technique by monitoring the absorbance-time profiles at the isosbestic point of the I2/I3(-) system (468 nm). Using the well-accepted rate coefficients of iodine hydrolysis, we have proven that iodine is the kinetically active species of the iodine-arsenous acid reaction. Strong iodide inhibition of this system is explained by a rapidly established equilibrium between iodine and arsenous acid to produce an iodide ion, a hydrogen ion, and a short-lived intermediate H2AsO3I, which is shifted far to the left. Taking into consideration the generally accepted kinetic model of the Dushman reaction where I2O2 plays a key role to account for all of the most important observations in this subsystem and a sequence of simple formal oxygen-transfer reactions between arsenous acid and iodic acid as well as iodous acid and hypoiodous acid, we propose a 13-step comprehensive kinetic model, including seven rapidly established equilibria with only six fitted parameters, that is able to explain all of the most important characteristics of the kinetic curves of all of the title systems both individually and simultaneously.

Comparative studies of the chemical consequences of activation of the halogens by the (n, gamma ) and (n,2n) processes have been extended to solutions of iodine in hydrocarbons. In contrast to the alkyl iodide system where no difference in chemistry between the two modes of activation was observed, (n,2n) activation results in this case in an appreciably higher organic yield. The observed increase in organic activity is attributed to the greater local disruption caused by the more energetic recoil atoms. (auth)

A procedure is presented for separating yttrium from the lanthanum group of rare earth elements by precipitating the latter as iodates. Yttrium remains in solution and is determined separately. In fission product mixtures that have cooled a year or longer, Pm147 can be determined readily after the separation of the lanthanum group elements from yttrium. Other applications of the general technique are suggested.

Preparation de iodo-6 naphtol-2, (iodo-6 methoxy-2) naphtalene, et diiodo-1,6 methoxy-2 naphtalene

Temperature composition data for the binary AgIO/sub 3/AgNO/sub 3/ are plotted. Above 65 weight% AgIO/sub 3/, a true solution could not be obtained at 300 deg C, the highest temperature used. A number of ternary compositions were also analyzed. The lowest melting eutectic occurred at a weight percent composition of 50% AgI--27% AgNO/sub 3/-- 23% AgIO/sub 3/ with a melting point of 76 deg C. (P.C.H.)