Chapter 8 Atomic StructureThree objectives:To describe the movement states of electronsTo introduce the electron configurationsTo reveal the relationship between theelectronic structure and periodicity
1 Chapter 8 Atomic Structure Three objectives: ◼ To describe the movement states of electrons ◼ To introduce the electron configurations ◼ To reveal the relationship between the electronic structure and periodicity
1 Movements of Electrons inAtomsSolutions:Experiments → ConclusionsApplying the quantum numbers obtaining fromthe Schrodinger equation to describe.Movements of submicroscopic particless (r< 10-8m) aredifferent from macroscopical objects
2 1 Movements of Electrons in Atoms Solutions: Experiments → Conclusions Applying the quantum numbers obtaining from the Schrödinger equation to describe. Movements of submicroscopic particles (r < 10-8m) are different from macroscopical objects
Cavendish卡文迪什实验室ErnestRutherford卢瑟福(1871-1937)in1908JosephJohnFatheroftheAtomicThomson汤姆孙andNuclearPhysics(1856～1940)all scienceiseitherphysics orstampt-collectingNiels BohrOttoStern斯特恩E.Schrodinger薛定(1885-1962)(1887-1961)n1933(1888-1969)In1943玻尔In1922
3 玻尔In 1922 Otto Stern斯特恩 (1888–1969 )In 1943 E.Schrödinger 薛定谔 (1887-1961）In 1933 Ernest Rutherford 卢瑟福 （1871-1937) in 1908 Father of the Atomic and Nuclear Physics ‘all science is either physics or stampt-collecting’ Joseph John Thomson汤姆孙 （1856～1940) Cavendish 卡文迪什实验室
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l-1CharacteristicsofElectronMovements1-1-1TheEnergyofElectronsinAtomsIsQuantized量子性Detector(photographicplate)ArcHighvoltageSlitHydrogen gasPrism410nm434nm486nm656nmFigure8-1Experimentaldevicegeneratingthehydrogenspectrum andthehydrogen linespectrum containsonlyafew discrete wavelengths invisiblelightrange(1885,SwissphysicistBalmer).5
5 1-1 Characteristics of ElectronMovements 1-1-1The Energy of Electrons in Atoms Is Quantized量子性 Figure 8-1 Experimental device generating the hydrogen spectrum and the hydrogen line spectrum contains only a few discrete wavelengths in visible light range(1885, Swiss physicist Balmer)
In1913,SwedenphysicistRydbergV=C/入=R（1/n2-1/n2)=3.289×1015（1/n2-1/n22)RydbergconstantR=3.289×1015s-1:n1,n2arepositiveintegrals,and n2≥n1E-0E4mPaschen spectral linesE3Balmerspectral linesE2-2LymanspectrallinesE.6
6 ◼ In 1913, Sweden physicist Rydberg v = c/ = R (1/n1 2 - 1/n2 2 ) = 3.289 1015 (1/n1 2 - 1/n2 2 ) Rydberg constant R = 3.289 1015 s -1 ; n1 , n2 are positive integrals, and n2 > n1 . n= ∞ n= 2 n= 3 n= 4 n= 1 E∞= 0 E4 E3 E2 E1 Lyman spectral lines Paschen spectral lines Balmer spectral lines
根据经典物理学概念：电子在运动过程中要发射电磁波，氢原子光谱应为连续光谱；带电微粒在力场中运动时总要产生电磁辐射并逐渐失去能量，运动着的电子轨道会越来越小，最终将与原子核相撞并导致原子Anunsatisfactoryatomicmodel毁灭.由于原子毁灭的事实从未发生而且原子光谱是线状，且有规律性这些都是经典物理学概念无法解释的
7 An unsatisfactory atomic model 根据经典物理学概念： ⚫电子在运动过程中要发射电磁 波，氢原子光谱应为连续光谱； ⚫带电微粒在力场中运动时总要 产生电磁辐射并逐渐失去能量, 运动着的电子轨道会越来越小, 最终将与原子核相撞并导致原子 毁灭. 由于原子毁灭的事实从未发生而且原子光谱是线状,且有规律性。 这些都是经典物理学概念无法解释的
玻尔理论建立在普朗克的量子论和爱因斯坦的光子学说的基础上：量子论：物质吸收和发射能量是不连续的，即物质只能以一最小单位(hv)一份一份的方式吸收或发射能量，能量最小的单位是光量子。爱因斯坦的光子学说认为光既是一种波，又有粒子性。E=hvE一光量子的能量V一光的频率一 光的波长p一光量子的动量h一普兰克常数8
8 量子论：物质吸收和发射能量是不连续的，即物质只能以 一最小单位(hν)一份一份的方式吸收或发射能量，能量最小 的单位是光量子。 玻尔理论建立在普朗克的量子论和爱因斯坦的 光子学说的基础上： 爱因斯坦的光子学说认为光既是一种波，又有粒子性。 E=hν Ｅ－ 光量子的能量 ν － 光的频率 p － 光量子的动量 λ－ 光的波长 h— 普兰克常数
The Bohr model includes two points:O(1) Electron in a hydrogen moves around the nucleus only incertain allowed circular orbits which must meet thefollowing requirement, each orbit was assigned a numbercalledtheprincipalquantumnumbern（主量子数)：mrv = nh / 2元n=1,2,3..m is mass of an electron;ris the distance from an electron to the nucleus;vis speed of electron;h = 6.626 ×10-34 J·s (Plank constant)
9 The Bohr model includes two points: (1) Electron in a hydrogen moves around the nucleus only in certain allowed circular orbits which must meet the following requirement, each orbit was assigned a number called the principal quantum number n (主量子数) : mrv = nh / 2π n=1,2,3. m is mass of an electron; r is the distance from an electron to the nucleus; v is speed of electron; h = 6.626 10-34 J∙s (Plank constant)
(2) When the electron is in the lowest energy orbit, thehydrogen atom is said to be in its ground state(基态)As energy (electromagnetic, thermal, or electrical) isadded to the atom, the electron is raised to higherand higher energy levels(能级) farther and higherfrom the nucleus. When the electron is in any higherenergy level, the hydrogen atom is said to be in anexcited state(激发态)v= (Efrinal - Einitial) / h10
10 (2) When the electron is in the lowest energy orbit, the hydrogen atom is said to be in its ground state(基态). As energy (electromagnetic, thermal, or electrical) is added to the atom, the electron is raised to higher and higher energy levels(能级) farther and higher from the nucleus. When the electron is in any higher energy level, the hydrogen atom is said to be in an excited state(激发态). v = (Efinal - Einitial) / h