Silicon is usually found to be four-coordinated when neighbored with oxygen. Six-coordinated silicon is only seen in samples at very specific composition or made at high temperature/pressure. In this study, we managed...Silicon is usually found to be four-coordinated when neighbored with oxygen. Six-coordinated silicon is only seen in samples at very specific composition or made at high temperature/pressure. In this study, we managed to synthesize calcium phosphosilicate xerogels containing six-coordinated silicon with the help of polyols by sol-gel method, without the need of treatment at high temperature or high pressure. Both phosphorus precursors and polyols were found to be essential for the formation of six-coordinated silicon species; in the absence of either species, only normal four-coordinated silicon was observed under otherwise identical conditions. Samples containing six-coordinated silicon sites were found to release silicon species faster than those without six-coordinated silicon sites upon dissolved in water, suggesting that six-coordinated silicon species have higher reactivity toward hydrolysis.展开更多
The crystal structure of silver（Ⅱ） 5,10,15,20-tetra（ethoxycarbonyl）porphyrin （Ag[Ⅱ]TECP） revealed it formed a one-dimensional coordination polymer through weak Ag-O interactions with an unusual six-coordinated...The crystal structure of silver（Ⅱ） 5,10,15,20-tetra（ethoxycarbonyl）porphyrin （Ag[Ⅱ]TECP） revealed it formed a one-dimensional coordination polymer through weak Ag-O interactions with an unusual six-coordinated central silver（Ⅱ） atom.展开更多
基金supported by the State Key Development Program of Basic Research of China (No.2012CB933200)National Natural Science Foundation of China (No.51173193)
文摘Silicon is usually found to be four-coordinated when neighbored with oxygen. Six-coordinated silicon is only seen in samples at very specific composition or made at high temperature/pressure. In this study, we managed to synthesize calcium phosphosilicate xerogels containing six-coordinated silicon with the help of polyols by sol-gel method, without the need of treatment at high temperature or high pressure. Both phosphorus precursors and polyols were found to be essential for the formation of six-coordinated silicon species; in the absence of either species, only normal four-coordinated silicon was observed under otherwise identical conditions. Samples containing six-coordinated silicon sites were found to release silicon species faster than those without six-coordinated silicon sites upon dissolved in water, suggesting that six-coordinated silicon species have higher reactivity toward hydrolysis.
基金financial support from the National Natural Science Foundation of China(Nos.21371059,21376099,21671068)
文摘The crystal structure of silver（Ⅱ） 5,10,15,20-tetra（ethoxycarbonyl）porphyrin （Ag[Ⅱ]TECP） revealed it formed a one-dimensional coordination polymer through weak Ag-O interactions with an unusual six-coordinated central silver（Ⅱ） atom.
