【摘要】 本文用CNDO/2法,研究了不同金属离子对硅桥氧键(Si—O^br)及硅端氧键(Si-O^ter)的影响。得到了硅酸盐骨架中硅氧键的性质与氧的成键状态、配位数以及金属离子影响之间的规律性。用得到的这些规律,可望较好地研究矿物学、地球化学、硅酸盐材料及冶金炉渣结构等同题。更多还原

【Abstract】 The effect of various metallic cations on siiicon—bridge oxygen (Si—O^br) bond and silicon—terminal oxygen (Si—O^ter bond is studied with CNDO/2 calculation method.The conciusions are:1) The characters of Si—O bonds are almost completely determined by the bonding states of oxygen. When O^br and O^ter are bi-coordinated and ∠Si—O—H≤∠Si—O—Si in standard molecule, Si—O^br bond is stronger than Si—O^terd onb.2) Any third coordination cation on O^br would weaken Si—O^br bond. Cations with larger electronegativities on O^br with bigger coordination number usually act more violently.3) Al—O^br bond is much weaker than Si—O^br bond in alumino-silicates. Al—O^br bond and Si—O^br bond are weakened strongly when there exists a third coordination cation on O^br.4) The strengths of Si—O^ter bond and Al—O^ter bond depend on ∠Si（Al）—O—M angles. The larger the angles, the stronger the bonds. Coordination cations on O^ter have no obvious effect on the properties of Si—O^br bond and Al—O^br bond. When O^ter with larger ∠Si—O—M angle is coordinated with cations with smaller electronegativities can strengthen Si—O^terM bond.5) The coordination cations on O^br or O^ter have a strong effect on the nearby bonds, but their effect on the next nearby bonds can be neglected.更多还原