Mechanical Shock. 
          Mechanical Vibration and Shock Series, Vol II.

Novel isotropic conductive adhesives (ICAs) filled with metal-coated polymer spheres (MPS) have been introduced in order to improve the mechanical performance, and hence the reliability, compared to conventional ICAs filled with solid silver (Ag) particles. This paper summarizes a number of characterization studies on the electrical, the mechanical and the rheological properties, as well as a study on the reliability, of MPS-based ICAs. The feasibility of the ICAs filled with MPS has been demonstrated in terms of potential processing capabilities, improved mechanical performance and competitive electrical properties (compared to conventional ICAs with Ag flakes). Therefore, the MPS-based ICAs have a good potential for demanding environment applications, in which electronic products (e.g., hand held devices) are subjected to thermal shock and thermal cycling, mechanical vibration and mechanical shock.

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Xenon Trioxide Adducts of O-Donor Ligands; [(CH3)2CO]3XeO3, [(CH3)2SO]3(XeO3)2, (C5H5NO)3(XeO3)2, and [(C6H5)3PO]2XeO3

10.26434/chemrxiv.7092263.v1 ◽

2018 ◽

Author(s):

Katherine Marczenko ◽

James Goettel ◽

Gary Schrobilgen

Keyword(s):

Room Temperature ◽

Triphenylphosphine Oxide ◽

Donor Ligands ◽

Mechanical Shock ◽

X Ray Diffraction ◽

X Ray ◽

Oxygen Coordination ◽

Xenon Trioxide ◽

Distorted Octahedra ◽

Coordination Spheres

Oxygen coordination to the Xe(VI) atom of XeO3 was observed in its adducts with triphenylphosphine oxide, dimethylsulfoxide, pyridine-N-oxide, and acetone. The crystalline adducts were characterized by low-temperature, single-crystal X-ray diffraction and Raman spectroscopy. Unlike solid XeO3, which detonates when mechanically or thermally shocked, the solid [(C6H5)3PO]2XeO3, [(CH3)2SO]3(XeO3)2, and (C5H5NO)3(XeO3)2 adducts are insensitive to mechanical shock, but undergo rapid deflagration when ignited by a flame. Both [(C6H5)3PO]2XeO3 and (C5H5NO)3(XeO3)2 are air-stable whereas [(CH3)2SO]3(XeO3)2 slowly decomposes over several days and [(CH3)2CO]3XeO3 undergoes adduct dissociation at room temperature. The xenon coordination sphere of [(C6H5)3PO]2XeO3 is a distorted square pyramid which provides the first example of a five-coordinate XeO3 adduct. The xenon coordination spheres of the remaining adducts are distorted octahedra comprised of three Xe---O secondary contacts that are approximately trans to the primary Xe–O bonds of XeO3. Quantum-chemical calculations were used to assess the Xe---O adduct bonds, which are predominantly electrostatic σ-hole bonds between the nucleophilic oxygen atoms of the bases and the σ-holes of the xenon atoms.

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