原子物理学第四版全套配套课件杨福家t3

Let me try,Find out about yourself. “I have a dream.“,The most beautiful thing we can experience is the Mysterious. It is the source of all true Art and Science. - Albert Einstein,2500 years ago The Revolution in human thinking “What is the world made of ?“ led to the birth of natural science.,博学而笃志 切问而近思,J. J. Thomson: the first man to open the gate leading to Particle Physics.,The Thomson Atom,Ernest Rutherford,Stability Identity Regeneration,Determination, doggedness & hard work are the characteristics that are highly valued in a group. Imagination puts the icing on the cake. - Leon Lederman,莱德曼： 坚定的信念、顽强奋斗、努力工作，都是在一个集体中倍受称赞的品德，再加上想象力，那就是锦上添花了。,The need of metallurgy and astronomy have promoted much research on heat radiation. Whether steel-making is good or bad depends on the T of the furnace and the T is indicated by the color of the flame. similarly, astronomers determine the surface T of stars by measuring the I distributions of the radiations from these stars.,Simulation of blackbody radiation,William Shakespeare,Birthplace,“The Merchant of Venice” Shylock, loanshark,Illustration of Wiens displacement law of blackbody radiation,Radiation energy density - frequency Wien's Displacement Law of Blackbody Radiation. T = 0.2898 / c Vm When T = 1000K Vm = 1.035*1014 Hz T: Absolute temperature of a blackbody Vm: Corresponding to the max radiation energy density,1899: Rayleigh & Jeans Radiation energy density E(, T) in a frequency interval d between & + d,E(, T),Comparison of the Rayleigh-Jeans formula and the Planck formula with experiment(points),“ultra-violet catastrophe”,Oct. 19, 1900 Planck:,E(, T),Max Planck (1858 - 1947) 1918 Nobel Prize Winner,Dec. 14, 1900: E = nh n = 1,2, h = 6.55 10-34 J S Electromagnetic radiation in its emission (& absorption) could only be in Quanta (certain discrete, fixed units of energy h),Albert Einstein (1879 - 1955) 摄于1905年, 1921 Nobel,1887 H. R. Hertz: Photoelectric Effect,An experimental arrangement for observing the photoelectric current,V: stopping potential,If light was entirely wave-like, we would expect that turning down the brightness of the light would cause slower electrons to be emitted. In fact, even very faint light produces fast electrons.,Slope = h,Dec. 14, 1900: E = nh n = 1,2, h = 6.55 10-34 J S Electromagnetic radiation in its emission (& absorption) could only be in Quanta (certain discrete, fixed units of energy h).,1887 H. R. Hertz: Photoelectric Effect,An experimental arrangement for observing the photoelectric current,Spectrum of Light,Isaac Newton (1642 - 1727),Newton: The only way for us to understand the structure inside matter is to investigate its light spectrum.,Figure 3.8 Schematic diagram of a prism spectrograph,In 1885, 14 spectral lines (14 frequencies) from hydrogen has been observed. J. J. Balmer put forward an empirical formula:,Empirical constant,or:,Spectrum of a hydrogen atom,J. R. Rydberg 1889:,RH: Rydberg constant; T: term value,n = 2 Balmer series (1885) n = 1 Lyman series (1906) n = 3 Paschen series (1908) n = 4 Brackett series (1922) n = 5 Pfund series (1924),Empirical expression for the H spectral lines N. Bohr obtained “the last & decisive piece of the jig-saw puzzle“,N. Bohr's Model: Classical Orbits with Stationary State Conditions (Concept of Quantum State) Frequency Condition (Quantum Transition) Quantization of Angular Momentum (Correspondence Principle),Centripetal Force,Coulomb Attraction,Frequency for e rotating in circular orbits,(7-1),(7-2),Radiation condition, Bohr postulated:,Compare Rydberg:,we obtained:,(7-3),(7-4),Atomic stepladder,Rydberg formula has the meaning: it represents the energy released when an electron jumps from one stationary state n' (with energy En') to another stationary state n (En).,From,we have,(7-5),Corresponding Principle: Phenomena in the atomic field & phenomena in the macroscopic domain may follow their respective own rules, but when the rules in the microscopic field are extended to the classical field, the numerical results obtained from such rules should agree with the results from the classical rules.,Rydberg:,When n is very large, & n' = n + 1 (n, n' is two adjacent states),(7-6),According to C. P., it must be,so, which should be (7-5),Thus,(7-7),&,(7-8),(7-9),Composit Constant c = 197 fm MeV = 197 nmeV e2 = 1.44 fm MeV mc2 = 0.511 MeV,(7-10),First Bohr Orbit of H:,(7-11),(1Å = 10-8 cm),E of e in H,(7-12),Define,Fine Structure Constant,(7-13),Dimensionless Constant mp / me & are 2 most important constant in Atomic Physics,(7-14),For H,(7-15),When n = 1,n = 2 Balmer series (1885) n = 1 Lyman series (1906) n = 3 Paschen series (1908) n = 4 Brackett series (1922) n = 5 Pfund series (1924),Binding E of the ground state of e in H, if we define it is 0, then,The E needs to move e in the g.s. of H to ,Energy level diagram of a hydrogen atom,Orbits and spectral lines of a hydrogen atom,Centripetal Force,Coulomb Attraction,Rotations of the