Density functional theory calculations are conducted to investigate the stability and interactions among small helium (He) clusters in bulk tungsten (W). The lowest energy structure of each cluster for sizes n= 1 ...Density functional theory calculations are conducted to investigate the stability and interactions among small helium (He) clusters in bulk tungsten (W). The lowest energy structure of each cluster for sizes n= 1 to 6 is determined. With the formation of He dusters, He defects form in bulk W. Tile thermodynamics of the dusters are investigated in the temperature range of 1000-2300K using molecular dynamics. This study provides the information essential to understand smaB He duster behavior in bulk W.展开更多
The reaction of [Et4N]2WOS3 with three equiv.of CuI and dmpzm in MeCN afforded [WOS3Cu3I(dmpzm)2]·2(MeCN)0.5(1·2(MeCN)0.5) while that of [PPh4]2WS4 with four equiv.of CuI in DMF/MeCN followed by the ...The reaction of [Et4N]2WOS3 with three equiv.of CuI and dmpzm in MeCN afforded [WOS3Cu3I(dmpzm)2]·2(MeCN)0.5(1·2(MeCN)0.5) while that of [PPh4]2WS4 with four equiv.of CuI in DMF/MeCN followed by the addition of two equiv.of dmpzm in MeOH gave rise to [WS4Cu4I2(dmpzm)2]·DMF(2·DMF).Both compounds were characterized by elemental analysis,IR,and single-crystal X-ray diffraction analysis.1·2(MeCN)0.5 crystallizes in triclinic,space group P1-with a = 11.4552(5),b = 11.6735(3),c = 16.2278(9) ,α = 99.537(9),β = 101.986(2),γ = 118.464(13)o,V = 1775.5(3)3,Z = 2,μ = 6.080 mm-1,Dc = 1.983 Mg/m3,T = 193(2) K,C24H35Cu3IN9OS3W,Mr = 1063.22,F(000) = 1018,S = 1.060,R = 0.0376 and wR = 0.0870.2·DMF belongs to the orthorhombic system,space group Pmn21 with a = 22.145(4),b = 11.464(2),c = 7.7370(15) ,V = 1964.2(6)3,Z = 2,μ = 6.865 mm-1,Dc = 2.189 Mg/m3,T = 193(2) K,C25H39Cu4I2N9OS4W,Mr = 1301.72,F(000) = 1226,R = 0.0632,wR = 0.1706 and S = 1.130.1·2(MeCN)0.5 consists of one CuI and two [Cu(dmpzm)]+ fragments that are linked by [WOS3]2-species via six Cu-S bonds,forming a nido-like [WS3Cu3] core.2·DMF contains a saddle-shaped [WS4Cu4] core with two iodides coordinated at two Cu centers in a cis position and two dmpzm ligands being chelated at another two Cu centers in a cis position.展开更多
The accumulation of He on a W surface during keV-He ion irradiation has been simulated using cluster dynamics modeling. This is based mainly on rate theory and improved by involving different types of objects, adoptin...The accumulation of He on a W surface during keV-He ion irradiation has been simulated using cluster dynamics modeling. This is based mainly on rate theory and improved by involving different types of objects, adopting up-to-date parameters and complex reaction processes, as well as considering the diffusion process along with depth. These new features make the simulated results compare very well with the experimental ones. The accumulation and diffusion processes are analyzed, and the depth and size dependence of the He concentrations contributed by different types of He clusters is also discussed. The exploration of the trapping and diffusion effects of the He atoms is helpful in understanding the evolution of the damages in the near-surface of plasma-facing materials under He ion irradiation.展开更多
The complex Na2 [CrW3O4(O2CCH3)8]2·H2O (Mr = 2343. 80) crystallizes in monoclinic, space group P21/n with a=11. 206 (4 ), b=18. 016 (9), c=14. 465 (5) A, β=98. 00(3)°, V=2891. 9 A, Z=2, Dc=2. 69 g/cm3, F(00...The complex Na2 [CrW3O4(O2CCH3)8]2·H2O (Mr = 2343. 80) crystallizes in monoclinic, space group P21/n with a=11. 206 (4 ), b=18. 016 (9), c=14. 465 (5) A, β=98. 00(3)°, V=2891. 9 A, Z=2, Dc=2. 69 g/cm3, F(000) =2168. Final R= 0.043, Rw=0.049 for 3144 independent reflections with I】3σ(I).The complex anion contains two W3O4 core which were connected by two Cr atomsthrough four μ3-O atoms and eight bridging CH3COO- groups. Each of the Cr atomsand the W atoms is coordinated by six oxygen atome. The amons are linked by Na+cations to form one-dimensional infinite chain structure. The infrared spetrum of thecompound has been measured and rationally assigned.展开更多
Reaction of (NH4)2WOS3 with CuI and 4-tert-butylpyridine (4-bpy) in EtOH afforded a tetranuclear neutral cluster WOS3Cu3I(4-bpy)3·0.25EtOH. This compound was characterized by elementary analysis, IR, 1H NMR, TGA,...Reaction of (NH4)2WOS3 with CuI and 4-tert-butylpyridine (4-bpy) in EtOH afforded a tetranuclear neutral cluster WOS3Cu3I(4-bpy)3·0.25EtOH. This compound was characterized by elementary analysis, IR, 1H NMR, TGA, and its crystal structure was determined by X-ray single crystal diffraction. It belongs to monoclinic, space group P2/c with a=2.220 9(2) nm, b=1.364 66(11) nm, c=2.490 6(2) nm, β=104.953(2)°, V=7.292 9(12) nm3, Z=4. The title compound may be viewed as having a half-open cubane-like structure in which three Cu(4-bpy)+ units are linked by a triply-bridging WOS32- unit and a doubly-bridging iodine atom. CCDC: 266412.展开更多
Reaction of a preformed cluster [{(η5-C5Me5)WS3}3Cu7(MeCN)9](PF6)4 (1) in MeCN with LiCl and PPh3 gave rise to a tetranuclear cationic cluster [(η5-C5Me5)WS3{Cu(PPh3)}3Cl](PF6) (2). The title compound 2 was char...Reaction of a preformed cluster [{(η5-C5Me5)WS3}3Cu7(MeCN)9](PF6)4 (1) in MeCN with LiCl and PPh3 gave rise to a tetranuclear cationic cluster [(η5-C5Me5)WS3{Cu(PPh3)}3Cl](PF6) (2). The title compound 2 was char- acterized by elementary analysis, IR, UV-Vis, 1H NMR, and its crystal structure was determined by X-ray single crystal diffraction. It belongs to monoclinic, space group P21/c with a=1.7998(4) nm, b=2.0836(4) nm, c=1.9135(4) nm, β=113.63(3)°, V=6.574(3) nm3, Z=4. The cluster cation [(η5-C5Me5)WS3{Cu(PPh3)}3Cl]+ of 2 contains a strongly distorted, cubane-like structure [WS3Cu3Cl] in which one Cl weakly fills into the void of the nido-like [WS3Cu3] fragment with three relatively long Cu-Cl distances. CCDC: 270415.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 11605007the Funding from the China Scholarship Council under Grant No 201506465019
文摘Density functional theory calculations are conducted to investigate the stability and interactions among small helium (He) clusters in bulk tungsten (W). The lowest energy structure of each cluster for sizes n= 1 to 6 is determined. With the formation of He dusters, He defects form in bulk W. Tile thermodynamics of the dusters are investigated in the temperature range of 1000-2300K using molecular dynamics. This study provides the information essential to understand smaB He duster behavior in bulk W.
基金Supported by the National Natural Science Foundation of China (No. 20525101,20801038) "Soochow Scholar" Program of Suzhou University
文摘The reaction of [Et4N]2WOS3 with three equiv.of CuI and dmpzm in MeCN afforded [WOS3Cu3I(dmpzm)2]·2(MeCN)0.5(1·2(MeCN)0.5) while that of [PPh4]2WS4 with four equiv.of CuI in DMF/MeCN followed by the addition of two equiv.of dmpzm in MeOH gave rise to [WS4Cu4I2(dmpzm)2]·DMF(2·DMF).Both compounds were characterized by elemental analysis,IR,and single-crystal X-ray diffraction analysis.1·2(MeCN)0.5 crystallizes in triclinic,space group P1-with a = 11.4552(5),b = 11.6735(3),c = 16.2278(9) ,α = 99.537(9),β = 101.986(2),γ = 118.464(13)o,V = 1775.5(3)3,Z = 2,μ = 6.080 mm-1,Dc = 1.983 Mg/m3,T = 193(2) K,C24H35Cu3IN9OS3W,Mr = 1063.22,F(000) = 1018,S = 1.060,R = 0.0376 and wR = 0.0870.2·DMF belongs to the orthorhombic system,space group Pmn21 with a = 22.145(4),b = 11.464(2),c = 7.7370(15) ,V = 1964.2(6)3,Z = 2,μ = 6.865 mm-1,Dc = 2.189 Mg/m3,T = 193(2) K,C25H39Cu4I2N9OS4W,Mr = 1301.72,F(000) = 1226,R = 0.0632,wR = 0.1706 and S = 1.130.1·2(MeCN)0.5 consists of one CuI and two [Cu(dmpzm)]+ fragments that are linked by [WOS3]2-species via six Cu-S bonds,forming a nido-like [WS3Cu3] core.2·DMF contains a saddle-shaped [WS4Cu4] core with two iodides coordinated at two Cu centers in a cis position and two dmpzm ligands being chelated at another two Cu centers in a cis position.
基金supported by the Special Funds for Major State Basic Research Project of China(973)(Nos.2007CB925004 and 2008CB717802)the Knowledge Innovation Program of the Chinese Academy of Sciences(No.KJCX2-YW-N35)+2 种基金National Natural Science Foundation of China(No.11005124)the China Postdoctoral Science Foundation Funded Project(No.20100470863)Director Grants of CASHIPS.Part of the calculations were performed in the Center for Computational Science of CASHIPS
文摘The accumulation of He on a W surface during keV-He ion irradiation has been simulated using cluster dynamics modeling. This is based mainly on rate theory and improved by involving different types of objects, adopting up-to-date parameters and complex reaction processes, as well as considering the diffusion process along with depth. These new features make the simulated results compare very well with the experimental ones. The accumulation and diffusion processes are analyzed, and the depth and size dependence of the He concentrations contributed by different types of He clusters is also discussed. The exploration of the trapping and diffusion effects of the He atoms is helpful in understanding the evolution of the damages in the near-surface of plasma-facing materials under He ion irradiation.
文摘The complex Na2 [CrW3O4(O2CCH3)8]2·H2O (Mr = 2343. 80) crystallizes in monoclinic, space group P21/n with a=11. 206 (4 ), b=18. 016 (9), c=14. 465 (5) A, β=98. 00(3)°, V=2891. 9 A, Z=2, Dc=2. 69 g/cm3, F(000) =2168. Final R= 0.043, Rw=0.049 for 3144 independent reflections with I】3σ(I).The complex anion contains two W3O4 core which were connected by two Cr atomsthrough four μ3-O atoms and eight bridging CH3COO- groups. Each of the Cr atomsand the W atoms is coordinated by six oxygen atome. The amons are linked by Na+cations to form one-dimensional infinite chain structure. The infrared spetrum of thecompound has been measured and rationally assigned.
文摘Reaction of (NH4)2WOS3 with CuI and 4-tert-butylpyridine (4-bpy) in EtOH afforded a tetranuclear neutral cluster WOS3Cu3I(4-bpy)3·0.25EtOH. This compound was characterized by elementary analysis, IR, 1H NMR, TGA, and its crystal structure was determined by X-ray single crystal diffraction. It belongs to monoclinic, space group P2/c with a=2.220 9(2) nm, b=1.364 66(11) nm, c=2.490 6(2) nm, β=104.953(2)°, V=7.292 9(12) nm3, Z=4. The title compound may be viewed as having a half-open cubane-like structure in which three Cu(4-bpy)+ units are linked by a triply-bridging WOS32- unit and a doubly-bridging iodine atom. CCDC: 266412.
文摘Reaction of a preformed cluster [{(η5-C5Me5)WS3}3Cu7(MeCN)9](PF6)4 (1) in MeCN with LiCl and PPh3 gave rise to a tetranuclear cationic cluster [(η5-C5Me5)WS3{Cu(PPh3)}3Cl](PF6) (2). The title compound 2 was char- acterized by elementary analysis, IR, UV-Vis, 1H NMR, and its crystal structure was determined by X-ray single crystal diffraction. It belongs to monoclinic, space group P21/c with a=1.7998(4) nm, b=2.0836(4) nm, c=1.9135(4) nm, β=113.63(3)°, V=6.574(3) nm3, Z=4. The cluster cation [(η5-C5Me5)WS3{Cu(PPh3)}3Cl]+ of 2 contains a strongly distorted, cubane-like structure [WS3Cu3Cl] in which one Cl weakly fills into the void of the nido-like [WS3Cu3] fragment with three relatively long Cu-Cl distances. CCDC: 270415.