基态原子电子组态

(A级掌握) 斯莱特根据光谱数据，归纳出一套估算屏蔽系数σ的经验规律。 首先把各能级按下面方法分成若干组(同一括号内的能级处于同一组) (1s)(2s,2p)(3s,3p)(3d)(4s,4p)(4d)(4f)(5s,5p)(5d)余此类推.这些组被认为是从核向外依次排列的(即能量依次增高). 1. 处在被屏蔽电子的轨道外面的轨道组σ为零,即近似的认为外轨道组电子对内轨道组电子没有屏蔽作用. 2. 与被屏蔽电子处在同一轨道组的电子其σ为0.35(1s组除外,它是0.30) 3. 如果被屏蔽电子处在ns或np轨道上,则(n-1)轨道组的每个电子的σ为0.85,而更内的轨道组上的电子的σ则为1.00。 4. 如果被屏蔽电子处在nd或nf轨道上,则位于它左边各轨道组上的电子的σ均为1.00. 由上述经验数据可估算出某原子中其它电子对该电子的σ值,从而计算出对该电子相应的有效核电荷Z*的值以及电子或轨道能量. 例题1:计算说明基态钾原子(Z=19)的最后一个电子是排布在4s轨道还是3d轨道上, emotionalBecause of the guerrilla forces in the surrounding area have been withdrawn, activities in the Lake's Cheng Wanjun also refuge in Japanese, Zhu Xi forces became the puppet to attack key targets Eve puppet attacking in Wuzhen, face the problem of the retreat was to meet the enemy, in a debate within the leadership, some believe that the elves, concentrate a superior force, surely do, early transfer is the best way to reduce losses. Deputy Commander Wang Hesong impassioned statement: "Wuzhen hold, is our military's duty!" I have win a series of victories, morale, Wuzhen battle to victory, fight this battle, a Chinese miracle in the history of guerrilla warfare."Commander Zhu Xi did not have much, but the final word. On November 5, we flew over the town for several days, bomb bursts, trembling moan tranquil town in the war. People have the feeling of a catastrophe in the town. 6th reconnaissance around the command personnel brought an urgent intelligence, town-wide panic, in the face of news of the Japanese attack town, to avoid the scourge of war, the majority of people young and old fled to the countryside in the town. Also hard to find a boat in the river. Past the bustling town just seems a deserted and desolate. 7th day in implementing low-level flights over the town, fired. That night, the Elves attack Wuzhen confirmed information. Night, bursts of gunfire coming from the distance, reportedly is Deputy Commander Wang Hesong Xu Miao came Nanxun sniper assault of the Elves. 8th, the situation is more severe in the town. One afternoon, outside East Gate and South Gate there was intense gunfire. Enemy attacks by frustrated independent battalion confronted Chen qi. At this time, the command ... 11th, as Commander of Zhu Xi-Kai Wen Yongzhi, Director of 解:钾原子的核外电子排布分组如下: (1s2)(2s22p6)(3s23p6)(3d)(4s) 如果最后一个电子填充在4s上,则: σ=(8×0.85)+(10×1.00)=16.80 ? Z*=Z-σ=19-16.80=2.20 ? E4s=-(13.6×2.202)?42=-4.11(eV) 如果最后一个电子填充在3d上,则: σ=(2+8+8)×1.00=18.00 ? Z*=Z-σ=19-18.00=1.00 ? E3d=-(13.6×1.002)?32=-1.51(eV) 因E4s的能量低于E3d,按能量最低原则,电子应填充在能量低的轨道上.所以钾原子的最后 一个电子是填充在4s轨道上的. 例题2:估算基态铁原子(Z=26)的4s和3d轨道上的一个电子的σ值，Z*和轨道能量E。 解:基态铁原子的核外电子排布分组如下: (1s2)(2s22p6)(3s23p6)(3d6)(4s2) 对于4s上的一个电子 σ=(1×0.35)+(14×0.85)+(10×1.00)=22.25 ?Z*=Z-σ=26-22.25=3.75 ?E4s=-(13.6×3.752)?42=-11.95(eV) 对于3d上的一个电子 σ=(5×0.35)+(18×1.00)=19.75 ?Z*=Z-σ=26-19.75=6.25 ?E3d=-(13.6×6.252)?32=-59.03(eV) emotionalBecause of the guerrilla forces in the surrounding area have been withdrawn, activities in the Lake's Cheng Wanjun also refuge in Japanese, Zhu Xi forces became the puppet to attack key targets Eve puppet attacking in Wuzhen, face the problem of the retreat was to meet the enemy, in a debate within the leadership, some believe that the elves, concentrate a superior force, surely do, early transfer is the best way to reduce losses. Deputy Commander Wang Hesong impassioned statement: "Wuzhen hold, is our military's duty!" I have win a series of victories, morale, Wuzhen battle to victory, fight this battle, a Chinese miracle in the history of guerrilla warfare."Commander Zhu Xi did not have much, but the final word. On November 5, we flew over the town for several days, bomb bursts, trembling moan tranquil town in the war. People have the feeling of a catastrophe in the town. 6th reconnaissance around the command personnel brought an urgent intelligence, town-wide panic, in the face of news of the Japanese attack town, to avoid the scourge of war, the majority of people young and old fled to the countryside in the town. Also hard to find a boat in the river. Past the bustling town just seems a deserted and desolate. 7th day in implementing low-level flights over the town, fired. That night, the Elves attack Wuzhen confirmed information. Night, bursts of gunfire coming from the distance, reportedly is Deputy Commander Wang Hesong Xu Miao came Nanxun sniper assault of the Elves. 8th, the situation is more severe in the town. One afternoon, outside East Gate and South Gate there was intense gunfire. Enemy attacks by frustrated independent battalion confronted Chen qi. At this time, the command ... 11th, as Commander of Zhu Xi-Kai Wen Yongzhi, Director of 由上述计算结果看出:填充上电子后,3d电子的能量反而低于4s电子. 思: 1-6.1:为什么电子在空轨道中填充时应先填4s轨道,而一旦3d轨道中有电子填入,则4s轨道能量升高到反高于3d?(A级掌握) 二: 钻穿效应(C级重点掌握) 1:钻穿效应的定义 氢原子的4s,4p,4d,4f轨道几率径向分布图 象这种外层电子有机会钻到内部空间而靠近原子核的现象，通常称为钻穿作用(或穿透作用)。钻穿作用的大小对轨道的能量有明显的影响.电子钻得越深,它受其它电子的屏蔽作用就越小,而受核的吸引力越大,因而本身能量也就越低.所以说,钻穿作用越大的电子能量越低.这种由于电子的钻穿作用的不同而使其能量发生变化的现象,称为钻穿效应。 2:钻穿效应的影响(C级重点掌握) 由于钻穿效应的存在,会使得一些能量相近的能级发生交错现象.如:E3d>E4s 3d和4s轨道的几率径向分布图 同理:E4d>E5s;E4f>E6s 概括一下,能级交错现象有: EnsE4s (C)由于能级交错,核外电子不是按电子层顺序,而是按能级组顺序进行填充 (D)原子核外电子填充顺序和失去电子的顺序是一致的 二: 近似能级图与原子序数的关系(B级掌握) 我们把能量相等的原子轨道称为简并轨道。如p轨道是三重简并的，三条轨道最多可容纳6个电子(可写成np6);d轨道是五重简并的,五条轨道最多可容纳10个电子(可写成nd10);而f轨道是七重简并的，七条轨道最多可容纳14个电子(可写成nf14)。 上述能级图是假定所有不同元素的原子能级高低次序都是一样的，这是一种近似。事实上，不同原子中轨道能级高低次序不是完全一样的。 思考题: 1-6.3:不同元素的原子其相同能级(如1s能级)的能量都一样吗,为什么,(B级掌握) 1-6.4:上图中在Z,21时，3d能量高于4s，但Z?21后，Z越大，3d能量越低于4s，为什么,(A级掌握) 所需解决的问题:核外电子的排布情况用什么式子来表达, 三:核外电子排布式(C级重点掌握) (1).核外电子的电子排布式 用轨道符号表示,并在其右上角标上数字,代表能级上的电子数.如:Mg(Z=12)的电子排布式为:1s22s22p63s2,又可表示为:[Ne]3s2 注意:Cu(Z=29)的电子排布顺序为:1s22s22p63s23p64s13d10.但最终习惯表示成emotionalBecause of the guerrilla forces in the surrounding area have been withdrawn, activities in the Lake's Cheng Wanjun also refuge in Japanese, Zhu Xi forces became the puppet to attack key targets Eve puppet attacking in Wuzhen, face the problem of the retreat was to meet the enemy, in a debate within the leadership, some believe that the elves, concentrate a superior force, surely do, early transfer is the best way to reduce losses. Deputy Commander Wang Hesong impassioned statement: "Wuzhen hold, is our military's duty!" I have win a series of victories, morale, Wuzhen battle to victory, fight this battle, a Chinese miracle in the history of guerrilla warfare."Commander Zhu Xi did not have much, but the final word. On November 5, we flew over the town for several days, bomb bursts, trembling moan tranquil town in the war. People have the feeling of a catastrophe in the town. 6th reconnaissance around the command personnel brought an urgent intelligence, town-wide panic, in the face of news of the Japanese attack town, to avoid the scourge of war, the majority of people young and old fled to the countryside in the town. Also hard to find a boat in the river. Past the bustling town just seems a deserted and desolate. 7th day in implementing low-level flights over the town, fired. That night, the Elves attack Wuzhen confirmed information. Night, bursts of gunfire coming from the distance, reportedly is Deputy Commander Wang Hesong Xu Miao came Nanxun sniper assault of the Elves. 8th, the situation is more severe in the town. One afternoon, outside East Gate and South Gate there was intense gunfire. Enemy attacks by frustrated independent battalion confronted Chen qi. At this time, the command ... 11th, as Commander of Zhu Xi-Kai Wen Yongzhi, Director of 1s22s22p63s23p63d104s1. 练习: 1-6.5:对基态钙原子的电子排布式正确的是( ).(C级掌握) (A) 1s22s22p63s23p64s2 (B) 1s22s22p63s23p64s14p1 (C) 1s22s22p63s23p74s1 (D) 1s22s22p63s23p54s3 (2).轨道排布式 用一条下划短线"_"或?以及?表示一条原子轨道和用上下箭头分别表示两种不同自旋方向的电子.如氧原子的轨道排布图. 练习: 1-6.6:基态碳原子的电子排布正确的是( )(C级掌握) (A)(B)(C)(D) (3).价电子层构型 指能参与化学反应并用于成键的电子的排布式.所谓价电子层,对主族元素是指最外层的ns和np能级;对于副族是指最外层的ns和次外层的(n-1)d能级.如P(Z=15)的价电子构型为:3s23p3;Ni(Z=28)的价电子构型为:3d84s2. 思考题: 1-6.5:已知Cu的电子排布顺序为:[Ar]4s13d10，当Cu失去2个电子成为Cu2+时，应失去能量高的3d能级上的电子,所以其离子的电子排布式为:[Ar]4s13d8，这种说法对吗,(B级重点掌握) 练习: 1-6.7:写出下列原子的核外电子排布式，价电子构型以及其轨道排布式。(C级重点掌握) A:Ba(Z=56);B:Ag(Z=47); C:As(Z=33);D:V(Z=23);E:Mn2+(Z=25) F:Co3+(Z=27) 例6(C级重点掌握) [重点提示]:重点掌握能级组的分组并能熟练地由原子序数写出其核外电子排布式，轨道排布式，价电子构型。 emotionalBecause of the guerrilla forces in the surrounding area have been withdrawn, activities in the Lake's Cheng Wanjun also refuge in Japanese, Zhu Xi forces became the puppet to attack key targets Eve puppet attacking in Wuzhen, face the problem of the retreat was to meet the enemy, in a debate within the leadership, some believe that the elves, concentrate a superior force, surely do, early transfer is the best way to reduce losses. Deputy Commander Wang Hesong impassioned statement: "Wuzhen hold, is our military's duty!" I have win a series of victories, morale, Wuzhen battle to victory, fight this battle, a Chinese miracle in the history of guerrilla warfare."Commander Zhu Xi did not have much, but the final word. On November 5, we flew over the town for several days, bomb bursts, trembling moan tranquil town in the war. People have the feeling of a catastrophe in the town. 6th reconnaissance around the command personnel brought an urgent intelligence, town-wide panic, in the face of news of the Japanese attack town, to avoid the scourge of war, the majority of people young and old fled to the countryside in the town. Also hard to find a boat in the river. Past the bustling town just seems a deserted and desolate. 7th day in implementing low-level flights over the town, fired. That night, the Elves attack Wuzhen confirmed information. Night, bursts of gunfire coming from the distance, reportedly is Deputy Commander Wang Hesong Xu Miao came Nanxun sniper assault of the Elves. 8th, the situation is more severe in the town. One afternoon, outside East Gate and South Gate there was intense gunfire. Enemy attacks by frustrated independent battalion confronted Chen qi. At this time, the command ... 11th, as Commander of Zhu Xi-Kai Wen Yongzhi, Director of