计算机与应用化学
計算機與應用化學
계산궤여응용화학
COMPUTERS AND APPLIED CHEMISTRY
2013年
5期
565-569
,共5页
蒙特卡罗模拟%电极化%Metropolis方法%相对介电常量
矇特卡囉模擬%電極化%Metropolis方法%相對介電常量
몽특잡라모의%전겁화%Metropolis방법%상대개전상량
Monte Carlo simulation%electric polarization%Metropolis method%relative dielectric constant
使用蒙特卡罗方法模拟了极性电介质的极化现象，结果显示：系统达到平衡态后，倾向于电场方向的分子数增多，逆着电场方向的分子数减少，每个分子电矩的取向仍不断发生变化；电场越强，沿电场方向的分子数越多，电极化强度越大，电极化强度与场强成线性关系；场强不变时，温度越高，分子电矩取向越杂乱，电极化强度越小，说明电介质的极化率和介电常量随温度升高而减小。我们还对20℃、1 atm条件下CH3Cl、HBr、HCl、CH3Br、CH3I、CH3F、C2H5Cl、C2H3Cl 8种气体的相对介电常量作了估算，估算值和相应的实验值符合得较好，说明本文的模拟方法可较好地用来估算电介质气体的相对介电常量。
使用矇特卡囉方法模擬瞭極性電介質的極化現象，結果顯示：繫統達到平衡態後，傾嚮于電場方嚮的分子數增多，逆著電場方嚮的分子數減少，每箇分子電矩的取嚮仍不斷髮生變化；電場越彊，沿電場方嚮的分子數越多，電極化彊度越大，電極化彊度與場彊成線性關繫；場彊不變時，溫度越高，分子電矩取嚮越雜亂，電極化彊度越小，說明電介質的極化率和介電常量隨溫度升高而減小。我們還對20℃、1 atm條件下CH3Cl、HBr、HCl、CH3Br、CH3I、CH3F、C2H5Cl、C2H3Cl 8種氣體的相對介電常量作瞭估算，估算值和相應的實驗值符閤得較好，說明本文的模擬方法可較好地用來估算電介質氣體的相對介電常量。
사용몽특잡라방법모의료겁성전개질적겁화현상，결과현시：계통체도평형태후，경향우전장방향적분자수증다，역착전장방향적분자수감소，매개분자전구적취향잉불단발생변화；전장월강，연전장방향적분자수월다，전겁화강도월대，전겁화강도여장강성선성관계；장강불변시，온도월고，분자전구취향월잡란，전겁화강도월소，설명전개질적겁화솔화개전상량수온도승고이감소。아문환대20℃、1 atm조건하CH3Cl、HBr、HCl、CH3Br、CH3I、CH3F、C2H5Cl、C2H3Cl 8충기체적상대개전상량작료고산，고산치화상응적실험치부합득교호，설명본문적모의방법가교호지용래고산전개질기체적상대개전상량。
Polarization phenomenon in polar dielectrics is simulated by use of Monte Carlo method. The results show that when the system reaches equilibrium, the number of molecules inclined in the direction of the electric field increases, and the number of those in the opposite direction decreases. Orientations of molecular electric moments still constantly change. The stronger the electric field, the larger the number of molecules inclined to the direction of the electric field is, and the stronger the electric polarization intensity is. The electric polarization intensity is linear with the electric field strength. Maintaining a constant electric field, the higher the temperature, the more disordered the orientation of molecular electric moments is, and the weaker the electric polarization intensity is;that demonstrates the polarizability and the dielectric constant will be diminished with the temperature rise. The relative dielectric constants of CH3Cl, HBr, HCl, CH3Br, CH3I, CH3F, C2H5Cl and C2H3Cl are estimated at 20 ℃ and 1 atmosphere. The estimative values are in good agreement with the corresponding experimental values. That illustrates the simulation method can be used to estimate relative dielectric constants of dielectric gases.
