手征性物体中电偶极场的手征性排布

对手征性石英和螺旋铜丝的结构进行了分析研究.漆包铜丝本身由于铜和漆皮的接触起电效应,存在固有的电偶极场.当铜丝弯成手征性的螺旋结构时,其固有的场也转变成手征性排列,类似螺苯中C-H键的电偶极场分布.手性石英晶体中的SiO4四面体结构单元表现出扭转的手性结构,并且Si-O键有二种不同长度,结构参数的差值已超出误差范围.一块手性石英晶体相当于由无数的均匀手性的SiO4结构单元组成.SiO4结构单元的构像手性以及手征性偶极场排布也被揭示出来.研究说明,不仅手性分子中存在手征性的场分布,石英晶体和螺旋铜丝也存在固有的手征性偶极场分布.手征性偶极场的存在能够解释光学活性的起源问题.

Chiral Arrangement of Dipole Fields in Chiral Objects

The structures of chiral quartz and copper helices are analysized. Due to contact electrification effect, enamel-in- sulated copper wires possess intrinsic dipole fields. When copper wires are curved into the helical structures, the intrinsic dipole fields exist in handed forms,analogue to the handed arrangement of C--H dipoles of helicenes. The SiO4 tetrahedral units of quartz actually exhibit conformational chirality with a twist, and the two pair of Si--O bonds are different and the structural differences are larger than their uncertainties. A chiral quartz actually consists of homochiral SiO4 building blocks. The handed arrangement of Si---O dipoles is revealed in such SiO4 tetrahedron. It suggests that,not only chiral molecules but also chiral quartz and enamel-insulated copper helices possess handed distribution of dipole fields. The intrinsic handed dipole fields may be responsible for the origin of natural optical activity.