Min Zhang

Bio: Min Zhang is an academic researcher from Hunan University of Science and Engineering. The author has contributed to research in topics: Crystal structure & Iodide. The author has an hindex of 5, co-authored 38 publications receiving 65 citations.

Crystal structure of 2-(4-bromophenyl)-1,3-dimethyl-2,3-dihydro-1H-perimidine, C19H17BrN2

Abstract: Abstract C19H17BrN2, orthorhombic, Pnma, a = 11.506(5) Å, b = 12.176(5) Å, c = 11.327(5) Å, V = 1586.8(11) Å3, Z = 4, Rgt(F) = 0.0409, wRref(F2) = 0.1051, T = 296(2) K.

Crystal structure of 2-(4-chlorophenyl)-2,3-dihydro-1H-perimidine, C17H13Cl1N2

Abstract: Abstract C17H13BrN2, orthorhombic, Pbca (no. 61), a = 9.995(4) Å, b = 13.845(5) Å, c = 20.213(7) Å, V = 2797.2(18) Å3, Z = 8, Rgt(F) = 0.0304, wRref(F2) = 0.0784, T = 296(2) K.

Crystal structure of 2,8-diphenyl-3,7,9-trioxa-1-azaspiro[4.5]dec-1-ene, C18H17N1O3

Abstract: Abstract C18H17N1O3, monoclinic, P21/c (no. 14), a = 14.9752(8) Å, b = 9.0793(5) Å, c = 11.1030(6) Å, β = 106.431(1)°, V = 1447.96(14) Å3, Z = 4, Rgt(F) = 0.0342, wRref(F2) = 0.0903, T = 296(2) K.

Crystal structure of 1,3-dimethyl-2-(p-tolyl)-1H-perimidin-3-ium iodide 1.5 hydrate, C20H22IN2O1.5

Abstract: Abstract C20H22IN2O1.5, monoclinic, C2/c (no. 15), a = 38.828(4) Å, b = 9.5689(9) Å, c = 26.186(2) Å, β = 127.719(1)°, Z = 8, V = 7696.0(12) Å3, Rgt(F) = 0.0379, wRref(F2) = 0.1058, T = 296(2) K.

Crystal structure of 2-(4-methoxyphenyl)chromane, C16H16O2

Abstract: Abstract C16H16O2, monoclinic, P21/c (no. 14), a = 13.685(10) Å, b = 6.461(5) Å, c = 15.717(12) Å, β = 112.262(8)°, V = 1286.1(17) Å3, Z = 4, Rgt(F) = 0.0417, wRref(F2) = 0.1200, T = 296(2) K.

Validation of experimental molecular crystal structures with dispersion-corrected density functional theory calculations

Abstract: This paper describes the validation of a dispersion-corrected density functional theory (d-DFT) method for the purpose of assessing the correctness of experimental organic crystal structures and enhancing the information content of purely experimental data. 241 experimental organic crystal structures from the August 2008 issue of Acta Cryst. Section E were energy-minimized in full, including unit-cell parameters. The differences between the experimental and the minimized crystal structures were subjected to statistical analysis. The r.m.s. Cartesian displacement excluding H atoms upon energy minimization with flexible unit-cell parameters is selected as a pertinent indicator of the correctness of a crystal structure. All 241 experimental crystal structures are reproduced very well: the average r.m.s. Cartesian displacement for the 241 crystal structures, including 16 disordered structures, is only 0.095 A (0.084 A for the 225 ordered structures). R.m.s. Cartesian displacements above 0.25 A either indicate incorrect experimental crystal structures or reveal interesting structural features such as exceptionally large temperature effects, incorrectly modelled disorder or symmetry breaking H atoms. After validation, the method is applied to nine examples that are known to be ambiguous or subtly incorrect.

A Short History Of...

Abstract: There are very few people who have lived the allotted time but have an interesting biography, and there are very few congregations but have a very profitable history. The church at Leiper’s Fork, now known as Hillsboro, TN, has a most interesting history. There are few, if any, who know the history of their congregation. It seems that it would be encouraging to the congregation if its history would be kept fresh in the minds of its members.

Chloridobis(ethyl-enediamine-κN,N')(n-pentyl-amine-κN)cobalt(III) dichloride monhydrate.

Abstract: The title complex, [CoCl(C5H13N)(C2H8N2)2]Cl2·H2O, comprises one chloridobis(ethyl­enediamine)(n-pentyl­amine)cobalt(III) cation, two chloride counter-anions and a water mol­ecule. The CoIII atom of the complex is hexa­coordinated by five N and one Cl atoms. The five N atoms are from two chelating ethyl­enediamine and one n-pentyl­amine ligands. Neighbouring cations and anions are connected by N—H⋯Cl and N—H⋯O hydrogen bonds to each other and also to the water mol­ecule.