Working group report: Heavy-ion physics and quark-gluon plasma

This is the report of Heavy Ion Physics and Quark-Gluon Plasma at WHEPP-09 which was part of Working Group-4. Discussion and work on some aspects of quark-gluon plasma believed to have created in heavy-ion collisions and in early Universe are reported.     

6β‐Azido‐7α‐hydroxy‐17‐oxo‐5α‐androstan‐3β‐yl acetate

In the title compound, C₂₁H₃₁N₃O₄, a potential inhibitor of aromatase, all rings are fused trans. Rings A, B and C have chair conformations which are slightly flattened. Ring D has a 14α‐envelope conformation. The steroid nucleus has a small twist, as shown by the C19—C10⋯C13—C18 torsion angle of 6.6 (2)°. Ab initio calculations of the equilibrium geometry of the mol­ecule reproduce this small twist, which appears to be due to the steric effect of the 6β‐azide substituent rather than to packing effects.     

17‐Oxo‐5α‐androst‐6‐en‐3β‐yl acetate

In the title compound, C₂₁H₃₀O₃, a potential inhibitor of aromatase, all rings are fused trans. Rings A and C have chair conformations which are slightly flattened, whereas the conformation of ring B is close to a half‐chair. Ring D has a 14α‐envelope conformation. The steroid nucleus has a small twist, as shown by the C19—C10⋯C13—C18 (steroid numbering) torsion angle of −6.9 (3)°. Ab initio calculations of the equilibrium geometry of the mol­ecule reproduce this small twist, which appears to be due to the conformation of ring B rather than to packing effects.     

Weak antiferromagnetic inter­actions in hydro­nium diaqua‐1κO,2κO‐trichloro‐1κCl,2κ2Cl‐μ‐dimethyl­glycinato‐1κO:2κ2O′,N‐dimethyl­glycinato‐1κ2N,O‐dicuprate(II)

The crystal structure of the title compound, (H₃O)[Cu₂(C₄H₈NO₂)₂Cl₃(H₂O)₂], contains two Cu^II ions bridged by the carboxyl­ate group of a dimethyl­glycinate ion in an anti–anti configuration. The Cu^II atoms both have an approximately square‐pyramidal conformation geometry and are 5.977 (2) Å apart. The two dimethyl­glycinate ligands have similar conformations, although they play different roles in the structure. A weak antiferromagnetic inter­action between the two copper ions could be inferred from the magnetic susceptibility measurements.     

Crystal structure of the nonlinear optical compound L-arginine fluoride

L-arginine fluoride is a promising compound that exhibits nonlinear optical properties. It efficiently converts two single photons of the same polarization and frequency to one photon of frequency 2 (type I phase matching). C₆H₁₅N₄O₂ ⁺F^– is monoclinic, space group P2₁, a = 5.4475(4) Å, b = 8.5133(6) Å, c = 10.2195(7) Å, = 93.475(6)°. The cation has a zwitterionic form, protonated at both the guanidyl and amino groups. The arginine C atom is in a trans position to the carboxyl group. A complex three-dimensional hydrogen bond network links the anions and cations together.     

Crystal and molecular structure of 4,6-bis(nitroimino)-1,3,5-triazinan-2-one: theoretical and X-ray studies

This paper provides an overview of recent progress on structural data on the title compound. Theoretical work based on quantum mechanical calculations was performed to gain some understanding on the heterocyclic tautomerism potentially exhibited by the compound. The computational studies encompassed a wide range of tautomers/conformers, allowing the determination of the most probable molecular structure. In the gas phase, the nitroimine tautomers are computed to be substantially more stable than the nitramine tautomers. Among three plausible nitroimine forms, special attention was given to 4,6-bis(nitroimino)-1,3,5-triazinan-2-one, whose crystal structure was unequivocally solved by X-ray diffraction. The crystals are orthorhombic, space group Pnma with a = 6.187(2)A, b = 13.252(5)A, c = 8.802(4)A, and Z = 4. The structure was solved by direct methods and refined to a final R = 0.0326. The molecule has an approximate mirror plane relating the two symmetry related halves. The nitroimine groups are positioned in a syn-syn conformation. The least-squares (LS) plane of the heterocyclic ring and the nitroimine ([double bond]N-NO2) substituent LS plane make an angle of 10.05(11) degrees. The crystal structure is held together via hydrogen bonds that assemble the molecules in chains running along the b-axis. Every H-atom is involved in bifurcated hydrogen bonds.     

A ladder type structure: Rubidium diphenylacetate diphenylacetic acid

A new rubidium complex, rubidium diphenylacetate diphenylacetic acid has been synthesised and characterised by single-crystal X-ray diffraction: triclinic, P with a=7.437(3) ?, b=12.377(4) ?, c=14.384(3) ?, α=107.08(2)°, β=103.67(2)°, γ=96.95(3)°, Mr=508.93, V=1203.6(6) ?³, Z=2. The diphenylacetic molecules bridge the metallic ions forming an infinite ladder structure. Two strong hydrogen bonds link the organic moieties. Supplementary materials Crystallographic data for structural analysis have been deposited with the Cambridge Crystallographic Data Center, CCDC No. 602647. Copies of this information may be obtained free of charge on application to CCDC, 12 Union Road, Cambridge CB2 1EZ, UK (fax: +44 1223 336 033; e-mail: deposit@ccdc.cam.ac.uk or http://www.ccdc.cam.ac.uk).