Teleseismic receiver function analysis of seismograms recorded on a ∼700 km long profile of 17 broadband seismographs traversing the NW Himalaya shows a progressive northward deepening of the Indian Moho from ∼40 km beneath Delhi south of the Himalayan foredeep to ∼75 km beneath Taksha at the Karakoram Fault. Similar studies by Wittlinger et al. (2004) to the north of the Karakoram Fault show that the Moho continues to deepen to ∼90 km beneath western Tibet before shallowing substantially to 50–60 km at the Altyn Tagh Fault. The continuity of the Indian Moho imaged in the receiver functions reported here, along with those of Wittlinger et al. (2004), suggest that in this part of the Himalayan orogen the Indian plate may penetrate as far as the Bangong Suture, and possibly as far north as the Altyn Tagh.

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1,2,4,5-Tetrakis(phenyselenomethyl)benzene (L) has been synthesized by reaction of in situ generated PhSe(-) with 1,2,4,5-tetrakis(bromomethyl)benzene in N(2) atmosphere. Its first bimetallic complexes and a bis-pincer complex having compositions [(η(3)-C(3)H(5))(2)Pd(2)(L)][ClO(4)](2) (1) [Pd(2)(C(5)H(5)N)(2)(L)][BF(4)](2) (2) and [(η(6)-C(6)H(6))(2)Ru(2)(L)Cl(2)][PF(6)](2) (3) have been synthesized by reacting L with [Pd(η(3)-C(3)H(5))Cl](2), [Pd(CH(3)CN)(4)][BF(4)](2) and [(η(6)-C(6)H(6))(2)RuCl(2)](2) respectively. The structures of ligand L and its all three complexes have been determined by X-ray crystallography. In 1 and 3, ligand L forms with two organometallic species seven membered chelate rings whereas in 2 it ligates in a bis-pincer coordination mode. The geometry around Pd in 1 or 2 is close to square planar whereas in 3, Ru has pseudo-octahedral half sandwich "Piano-Stool" geometry. The Pd-Se bond distances are in the ranges 2.4004(9)-2.4627(14) Å and follow the order 1 > 2, whereas Ru-Se bond lengths are between 2.4945(16) and 2.5157(17) Å. The 1 and 2 have been found efficient catalysts for Heck reaction of aryl halides with styrene and methyl acrylate. The 2 is superior to 1. The TON and TOF values (per Pd) are up to ~47500 and ~2639 h(-1) respectively.

This paper presents a scheme to achieve THz radiation by the beating of cosh-Gaussian lasers in spatially periodic density plasma (ripple density). Here, the lasers exert a nonlinear ponderomotive force along the transverse direction which imparts an oscillatory velocity to electrons that couples with the density ripple to generate a stronger transient transverse current due to the spatial variation of their fields, driving THz radiation. The importance of laser-beam-width parameters, decentred parameter, amplitude and periodicity of the density structure are discussed for THz emission. By changing the decentred parameter the peak intensity of lasers can be shifted in the transverse direction and a notable change is found in the magnitude of THz field amplitude and its conversion efficiency.

Five new metal pyrazine complex templated Anderson−Evans cluster based solids, (Hpyz)[{Co(pyz)2(H2O)2}{CrMo6(OH)6O18}]·2H2O (7), (Hpyz)[{Zn(pyz)2(H2O)2}{CrMo6(OH)6O18}]·2H2O (8), [{Ni(pyz)(H2O)4}2{CrMo6(OH)6O18}](CH3COO)2·6H2O (9) (pyz = pyrazine), [Na(CrMo6(OH)8O16)]·10H2O (10), and (Hpyz)[{Ni(pyz)2(H2O)2}{CrMo6(OH)6O18}]·2H2O (11) were crystallized from aqueous solution by reacting sodium molybdate, chromium chloride, metal chloride, and pyrazine at room temperature. The crystal structure, phase purity, and thermal stability of the crystals were established by single-crystal and powder X-ray diffraction, elemental analysis, FTIR, TGA, and magnetic measurements. 7, 8, and 11 are isostructural and show covalently linked 1D anionic chains of alternating Anderson−Evans cluster and cationic complex, {M(pyz)2(H2O)2O2/2} (M = Co, Ni, and Zn); free protonated pyrazinium moieties provide additional counter-charge and further stability through nonbonding interactions. 9 is a rare example of a 1D coordination polymer of the composition {Ni(pyz)(H2O)4}2+ that supramolecularly aggregates with two counter anions, the discrete molybdate cluster and acetate, along with water molecules. 10 is a new pseudopolymorph of a sodium based chromium molybdate cluster exhibiting 2D layers; the sheets are held together by corrugated water sheets made of decameric water clusters. This paper discusses how weak interactions between aggregating tectons induce different supramolecular assemblies that eventually result in the nucleation of a crystal. The retrosynthetic analysis proposed here provides molecular insights to interpret the crystal engineering of these complex solids and directions for designing new solids in the system.

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Crystallization of solids, molecular or non-molecular from solution is a supramolecular reaction. Nucleation of a lattice structure at supersaturation can be conceived to result from a critical nucleus, a high energy intermediate (supramolecular transition state). Conceptualization of a structure for the critical nucleus in terms of aggregation of tectons through non-covalent interactions provides chemical insights into the architecture of a solid. The retrosynthetic analysis of copper-based minerals and materials offers an elegant description for the crystal packing. It addresses the influence of the geometry, functionality and reactivity of copper tecton(s) in directing a specific supramolecular aggregation. The mechanistic approach provides guiding principles to chemists to account for the experimentally crystallized solids and a platform to practice structure-synthesis correlation. Rationalization of the same composition with different atomic arrangements (polymorphs), compositional variation leading to different pseudopolymorphs, degree of hydration (anhydrous to hydrated), water clusters, role of solvent, etc. can all be justified on molecular basis. Also, the method gives predictive components including directions to synthesize new solids. In a nutshell, the paper is an attempt to generalize the crystallization of inorganic solids from solution by recognizing supramolecular interactions between metal tectons and gain insights for designing new MOF.