I.r. and e.s.r. spectra of γ-irradiated [Cr(CN)5NO]3–, [Mn(CN)5NO]3–, and [Fe(CN)5NO]2– in alkali-metal halide host lattices are reported. New i.r. absorptions are attributed to species resembling [Cr(CN)5NO]4–and 5– and [Mn(CN)5NO]2–and 4–. There is e.s.r. evidence for the formation of [Mn(CN)5NO]2– and [Fe(CN)5NO]3– ions, but no feature attributable to [Cr(CN)5NO]5– or [Mn(CN)5NO]4– was detected. Possible reasons for this apparent contradiction are discussed. There was evidence for the metal ion in [Mn(CN)5NO]3– migrating though the lattice to sites where it could exist in the high-spin d5 form.
{"title":"Infrared and electron spin resonance studies of the effect of γ-irradiation on [Cr(CN)5NO]3–, [Mn(CN)5NO]3–, and [Fe(CN)5NO]2– in alkali-metal halide host lattices","authors":"M. Bloom, J. Raynor, K. Root, M. Symons","doi":"10.1039/J19710003212","DOIUrl":"https://doi.org/10.1039/J19710003212","url":null,"abstract":"I.r. and e.s.r. spectra of γ-irradiated [Cr(CN)5NO]3–, [Mn(CN)5NO]3–, and [Fe(CN)5NO]2– in alkali-metal halide host lattices are reported. New i.r. absorptions are attributed to species resembling [Cr(CN)5NO]4–and 5– and [Mn(CN)5NO]2–and 4–. There is e.s.r. evidence for the formation of [Mn(CN)5NO]2– and [Fe(CN)5NO]3– ions, but no feature attributable to [Cr(CN)5NO]5– or [Mn(CN)5NO]4– was detected. Possible reasons for this apparent contradiction are discussed. There was evidence for the metal ion in [Mn(CN)5NO]3– migrating though the lattice to sites where it could exist in the high-spin d5 form.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":"26 1","pages":"3212-3216"},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80182847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The principal and mean magnetic susceptibilities of Co(py)2Cl2(py = pyridine) have been measured in the temperature range 300–80 K. They are characterized by an interesting anomaly at ca. 150 K when the crystal anisotropy in the ab plane abruptly changes sign. There is an associated transition in the anisotropy in the bc plane but none is observed for mean moments. The overall effect on principal molecular magnetic moments appears sufficiently small, however, not to interfere with the theoretical interpretation of the magnetism of Co(py)2Cl2 within the framework of a tetragonally squashed octahedron. The mean moment of Co(py)2Cl2 at room temperature is well known to be high compared with other ‘octahedral’ cobalt(II) ions and a discussion of this phenomenon in terms of the sense of tetragonality is presented as are some general comparisons with the preceding paper.
{"title":"Magnetic properties of cobalt(II) complexes. Part III. Crystal magnetic anisotropy of α-dichlorobis(pyridine)cobalt(II)","authors":"R. Bentley, M. Gerloch, J. Lewis, P. Quested","doi":"10.1039/J19710003751","DOIUrl":"https://doi.org/10.1039/J19710003751","url":null,"abstract":"The principal and mean magnetic susceptibilities of Co(py)2Cl2(py = pyridine) have been measured in the temperature range 300–80 K. They are characterized by an interesting anomaly at ca. 150 K when the crystal anisotropy in the ab plane abruptly changes sign. There is an associated transition in the anisotropy in the bc plane but none is observed for mean moments. The overall effect on principal molecular magnetic moments appears sufficiently small, however, not to interfere with the theoretical interpretation of the magnetism of Co(py)2Cl2 within the framework of a tetragonally squashed octahedron. The mean moment of Co(py)2Cl2 at room temperature is well known to be high compared with other ‘octahedral’ cobalt(II) ions and a discussion of this phenomenon in terms of the sense of tetragonality is presented as are some general comparisons with the preceding paper.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":"10 1","pages":"3751-3756"},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80345690","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. C. Hayward, H. Hill, J. M. Pratt, ROBERT J. P. Williams
Formation constants have been determined for the substitution of co-ordinated water in diaquocobinamide by ammonia and imidazole, in aquocobalamin by ammonia, and in cyanoaquocobinamide by ammonia, pyridine, imidazole, benzimidazole, and adenine; the last three bases can co-ordinate in the conjugate anion form. It is shown that the formation constants for the binding of ammonia are more sensitive to the nature of the trans-ligand than those for the binding of imidazole, and that the relative order of their formation constants can change as the trans-ligand is varied. Pseudo-first-order rate constants for the substitution of co-ordinated ammonia by water at 30° have been obtained for corrinoids with the following trans-ligands: H2O, 1·4 × 10-5 s–1; 5,6-dimethylbenzimidazole, 8·6 × 10-5 s–1; CN–, SO32–, and CH3–, 3 × 10–1 s–1. The order of ligands observed in the kinetic trans-effect parallels that for the thermodynamic trans-effect.
{"title":"The chemistry of vitamin B12. Part XII. The co-ordination of nitrogenous bases","authors":"G. C. Hayward, H. Hill, J. M. Pratt, ROBERT J. P. Williams","doi":"10.1039/J19710000196","DOIUrl":"https://doi.org/10.1039/J19710000196","url":null,"abstract":"Formation constants have been determined for the substitution of co-ordinated water in diaquocobinamide by ammonia and imidazole, in aquocobalamin by ammonia, and in cyanoaquocobinamide by ammonia, pyridine, imidazole, benzimidazole, and adenine; the last three bases can co-ordinate in the conjugate anion form. It is shown that the formation constants for the binding of ammonia are more sensitive to the nature of the trans-ligand than those for the binding of imidazole, and that the relative order of their formation constants can change as the trans-ligand is varied. Pseudo-first-order rate constants for the substitution of co-ordinated ammonia by water at 30° have been obtained for corrinoids with the following trans-ligands: H2O, 1·4 × 10-5 s–1; 5,6-dimethylbenzimidazole, 8·6 × 10-5 s–1; CN–, SO32–, and CH3–, 3 × 10–1 s–1. The order of ligands observed in the kinetic trans-effect parallels that for the thermodynamic trans-effect.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":"182 1","pages":"196-200"},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80352272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kinetic studies on the reaction of vanadium(III) with mercury(II), 2VIII+ 2HgII→ 2VIV+(HgI)2, in perchloric acid solutions of ionic strengths 2·0M(LiClO4) and 3·0M(NaClO4) are consistent with the mechanism (i)–(iii). VIII+ HgII [graphic omitted] VIV+ HgI(i), VIII+ HgI [graphic omitted] VIV+ Hg0(ii), VIV+ HgI [graphic omitted] VV+ Hg0(iii), Subsequent reactions Hg0+ HgII→(HgI)2, and VIII+ VV→ 2VIV are more rapid and are not rate determining. The rate law corresponding to (i)–(iii) is given by (iv). At low initial vanadium(IV) concentrations the [graphic omitted] second term in (iv) is negligible, but at high vanadium(IV) concentrations (>0·1M) the second term becomes dominant. Although the kinetics do not rule out the two-electron reaction VIII+ HgII→ VV+ Hg0 as an alternative to (iii), the consecutive one-electron changes V3+→ VO2+→ VO2+ are considered more likely.
{"title":"Mechanism of the reaction of vanadium(III) with mercury(II) in aqueous perchloric acid solutions","authors":"M. Green, W. Higginson, J. Stead, A. Sykes","doi":"10.1039/J19710003068","DOIUrl":"https://doi.org/10.1039/J19710003068","url":null,"abstract":"Kinetic studies on the reaction of vanadium(III) with mercury(II), 2VIII+ 2HgII→ 2VIV+(HgI)2, in perchloric acid solutions of ionic strengths 2·0M(LiClO4) and 3·0M(NaClO4) are consistent with the mechanism (i)–(iii). VIII+ HgII [graphic omitted] VIV+ HgI(i), VIII+ HgI [graphic omitted] VIV+ Hg0(ii), VIV+ HgI [graphic omitted] VV+ Hg0(iii), Subsequent reactions Hg0+ HgII→(HgI)2, and VIII+ VV→ 2VIV are more rapid and are not rate determining. The rate law corresponding to (i)–(iii) is given by (iv). At low initial vanadium(IV) concentrations the [graphic omitted] second term in (iv) is negligible, but at high vanadium(IV) concentrations (>0·1M) the second term becomes dominant. Although the kinetics do not rule out the two-electron reaction VIII+ HgII→ VV+ Hg0 as an alternative to (iii), the consecutive one-electron changes V3+→ VO2+→ VO2+ are considered more likely.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":"59 1","pages":"3068-3074"},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82092815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The title compound crystallises in the space group P42/n(C4h4), with Z= 8, in a unit cell of dimensions: a=b= 19·704 ± 0·006, c= 11·736 ± 0·008 A. The structure was solved from visually estimated photographic data by the heavy-atom method, and refined to R 11·1% for 938 independent reflections. The molecule has a sandwich-type configuration with the cyclopentadienyl ring on one side of the molybdenum, and the other ligands, which are roughly square planar, lying on the other side. The carbonyls are mutually cis.
{"title":"Crystal and molecular structure of dicarbonyl-π-cyclopentadienyliodo[tri(n-butyl)phosphine]molybdenum(II)","authors":"R. Fenn, J. Cross","doi":"10.1039/J19710003312","DOIUrl":"https://doi.org/10.1039/J19710003312","url":null,"abstract":"The title compound crystallises in the space group P42/n(C4h4), with Z= 8, in a unit cell of dimensions: a=b= 19·704 ± 0·006, c= 11·736 ± 0·008 A. The structure was solved from visually estimated photographic data by the heavy-atom method, and refined to R 11·1% for 938 independent reflections. The molecule has a sandwich-type configuration with the cyclopentadienyl ring on one side of the molybdenum, and the other ligands, which are roughly square planar, lying on the other side. The carbonyls are mutually cis.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":"1 1","pages":"3312-3315"},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82151890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The kinetics of the reaction of buta-1,3-diene with an aqueous solution of sodium hexacyanodinickelate(I) and the subsequent formation of butenes have been studied at 25° and at an ionic strength of 1·1. The kinetics of the removal of butadiene show that the slow step in complex formation is reaction (i), in which ki= 1·4 ± 0·1 l mol–1 s–1. The kinetics of the formation of the butenes are interpreted in terms of the rate-controlling reduction of two Ni2(CN)64–+ C4H6→(π-C4H6)Ni2(CN)64–(i), cyano-nickel intermediates, π1 and π2, containing a π-1-methylallyl ligand and a π-buta-1,3-diene ligand respectively. The two intermediates react by kinetically distinct paths yielding predominantly trans-but-2-ene, (π1), and cis-but-2-ene, (π2). The presence of a π-1-methylallylnickel complex in the reaction mixture has been confirmed by n.m.r. spectroscopy.
{"title":"Reduction of buta-1,3-diene by the hexacyanodinickelate(I) anion","authors":"D. Bingham, M. G. Burnett","doi":"10.1039/J19710001782","DOIUrl":"https://doi.org/10.1039/J19710001782","url":null,"abstract":"The kinetics of the reaction of buta-1,3-diene with an aqueous solution of sodium hexacyanodinickelate(I) and the subsequent formation of butenes have been studied at 25° and at an ionic strength of 1·1. The kinetics of the removal of butadiene show that the slow step in complex formation is reaction (i), in which ki= 1·4 ± 0·1 l mol–1 s–1. The kinetics of the formation of the butenes are interpreted in terms of the rate-controlling reduction of two Ni2(CN)64–+ C4H6→(π-C4H6)Ni2(CN)64–(i), cyano-nickel intermediates, π1 and π2, containing a π-1-methylallyl ligand and a π-buta-1,3-diene ligand respectively. The two intermediates react by kinetically distinct paths yielding predominantly trans-but-2-ene, (π1), and cis-but-2-ene, (π2). The presence of a π-1-methylallylnickel complex in the reaction mixture has been confirmed by n.m.r. spectroscopy.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":"20 1","pages":"1782-1788"},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82207341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Application of a long-advocated sphere-in-continuum model to MX lattices yields halide radii in good agreement with those actually observed in diffraction studies. Not only do the mean values agree, but observed fluctuations from constancy are reflected in the individual values calculated for each MX, a second-order effect.
{"title":"Ionic radii from a continuum model for alkali-metal halide lattices","authors":"D. Rosseinsky","doi":"10.1039/J19710000608","DOIUrl":"https://doi.org/10.1039/J19710000608","url":null,"abstract":"Application of a long-advocated sphere-in-continuum model to MX lattices yields halide radii in good agreement with those actually observed in diffraction studies. Not only do the mean values agree, but observed fluctuations from constancy are reflected in the individual values calculated for each MX, a second-order effect.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":"20 1","pages":"608-610"},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81301533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. C. March, D. A. Couch, K. Emerson, J. Fergusson, W. Robinson
Complexes have been formed between bivalent ions of cobalt, nickel, copper, zinc, mercury, and palladium and the the ligands 4,4′-dicarboxyethyl-3,3′,5,5′-tetramethyldipyrromethene (mpmH) and 3,4′-dicarboxyethyl-5-chloro-3′,4,5′-trimethyldipyrromethene (cpmH). The stereochemistry of these complexes has been investigated by measurement of magnetic susceptibility, and 1H n.m.r. spectra, and u.v. visible spectra. An X-ray determination of the crystal and molecular structure of the complex Pd(mpm)2 is reported. The palladium atom lies on a crystallographic centre of symmetry and is necessarily coplanar with the four co-ordinated nitrogen atoms of the ligand. The unique bidentate ligand is not planar.
{"title":"Dipyrromethene complexes of transition metals. Part II. Stereochemistry of complexes of cobalt(II), nickel(II), copper(II), zinc(II), cadmium(II), mercury(II), and palladium(II) and crystal structure analysis of the palladium complex","authors":"F. C. March, D. A. Couch, K. Emerson, J. Fergusson, W. Robinson","doi":"10.1039/J19710000440","DOIUrl":"https://doi.org/10.1039/J19710000440","url":null,"abstract":"Complexes have been formed between bivalent ions of cobalt, nickel, copper, zinc, mercury, and palladium and the the ligands 4,4′-dicarboxyethyl-3,3′,5,5′-tetramethyldipyrromethene (mpmH) and 3,4′-dicarboxyethyl-5-chloro-3′,4,5′-trimethyldipyrromethene (cpmH). The stereochemistry of these complexes has been investigated by measurement of magnetic susceptibility, and 1H n.m.r. spectra, and u.v. visible spectra. An X-ray determination of the crystal and molecular structure of the complex Pd(mpm)2 is reported. The palladium atom lies on a crystallographic centre of symmetry and is necessarily coplanar with the four co-ordinated nitrogen atoms of the ligand. The unique bidentate ligand is not planar.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":"2 1","pages":"440-448"},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81446362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Triperoxovanadates of the type MI[V(O–O)3(AA)],nH2O and MI3[V(O–O)3(AA)′],H2O [M1= NH4, K or Na;(AA)= phen or bipy; (AA)′= C2O4(phen = 1,10-phenanthroline, bipy = 2,2′-bipyridyl)] have been prepared by reaction of the ligands with solutions of metavanadates in hydrogen peroxide. The molar conductivities of these salts in aqueous solution show the presence of 1 : 1 and 3 : 1 electrolytes. The existence, splitting, and shift of some i.r. bands including, in the 550–650 cm–1 region, bands assigned to the [graphic omitted] group show that the peroxophen, bipy and oxalato-groups are co-ordinated as bidentate ligands. U.v. spectra, magnetic susceptibilities, and an X-ray analysis are also reported. These complexes, in which the vanadium is probably eight-co-ordinate, are compared with the corresponding niobium and tantalum derivatives.
{"title":"Peroxo-complexes: triperoxovanadates(V) complexes","authors":"J. Sala-Pala, J. Guerchais","doi":"10.1039/J19710001132","DOIUrl":"https://doi.org/10.1039/J19710001132","url":null,"abstract":"Triperoxovanadates of the type MI[V(O–O)3(AA)],nH2O and MI3[V(O–O)3(AA)′],H2O [M1= NH4, K or Na;(AA)= phen or bipy; (AA)′= C2O4(phen = 1,10-phenanthroline, bipy = 2,2′-bipyridyl)] have been prepared by reaction of the ligands with solutions of metavanadates in hydrogen peroxide. The molar conductivities of these salts in aqueous solution show the presence of 1 : 1 and 3 : 1 electrolytes. The existence, splitting, and shift of some i.r. bands including, in the 550–650 cm–1 region, bands assigned to the [graphic omitted] group show that the peroxophen, bipy and oxalato-groups are co-ordinated as bidentate ligands. U.v. spectra, magnetic susceptibilities, and an X-ray analysis are also reported. These complexes, in which the vanadium is probably eight-co-ordinate, are compared with the corresponding niobium and tantalum derivatives.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":"49 1","pages":"1132-1136"},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81460333","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Relationships are developed between non-rigorous C–O force constants and those of a quadratic general valence force field for metal carbonyls whose ligands are symmetry-equivalent. The equations are tested by reference to full calculations on MCO molecules and to data available for group VIA hexacarbonyls. Approximations involved give errors which are of the same order as experimental frequency errors. The associated normal co-ordinate treatment leads, as part of the same approximation, to the conclusion that non-rigorous force constants are valid and realistic quantities so long as the co-ordinate system is properly defined.
{"title":"Use and interpretation of non-rigorous force constants derived from C–O stretching frequencies of metal carbonyls. Part I. Symmetric carbonyls","authors":"J. Miller","doi":"10.1039/J19710001885","DOIUrl":"https://doi.org/10.1039/J19710001885","url":null,"abstract":"Relationships are developed between non-rigorous C–O force constants and those of a quadratic general valence force field for metal carbonyls whose ligands are symmetry-equivalent. The equations are tested by reference to full calculations on MCO molecules and to data available for group VIA hexacarbonyls. Approximations involved give errors which are of the same order as experimental frequency errors. The associated normal co-ordinate treatment leads, as part of the same approximation, to the conclusion that non-rigorous force constants are valid and realistic quantities so long as the co-ordinate system is properly defined.","PeriodicalId":17321,"journal":{"name":"Journal of The Chemical Society A: Inorganic, Physical, Theoretical","volume":"4 1","pages":"1885-1891"},"PeriodicalIF":0.0,"publicationDate":"1971-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81670330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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