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Using scanning tunneling microscopy we observe a stripe phase smoothly interfacing with a triangular 2 × 2 superstructure on the surface of 2H-NbSesingle crystal. Proximity-induced superconductivity is demonstrated in these new ordered structures by measurements of low-temperature tunneling spectra. The modulation of superconductivity by the reconstruction provides an opportunity to understand the interplay between superconductivity and charge orders. [ABSTRACT FROM AUTHOR]

HfMgMo WxO12 with , 1.0, 1.5, 2.0, and 2.5 are developed with a simple solid state method. With increasing the content of W, solid solutions of HfMgMo WxO12 crystallize in an orthorhombic structure for and a monoclinic structure for . A near-zero thermal expansion (ZTE) is realized for HfMgMo W O12 and negative coefficients of thermal expansion (NCTE) are achieved for other compositions with different values. The ZTE and variation of NCTE are attributed to the difference in electronegativity between W and Mo and incorporation of a different amount of W, which cause variable distortion of the octahedra and softening of the MoO4 tetrahedra, and hence an enhanced NCTE in the a- and c-axis and reduced CTE in the b-axis as revealed by Raman spectroscopy and x-ray diffraction. [ABSTRACT FROM AUTHOR]