Lecture January 18, This course. Getting to know you/me/those who will help you and expectations.

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1 Lecture January 18, 2017 This course. Getting to know you/me/those who will help you and expectations. Handouts: 1) How I best learn. 2) Some information and poster preference. 3) Syllabus 4) Schedule 5) Project #1

2 CHEM 362 Prof. Marcetta Darensbourg, Rm Phone # Descriptive Inorganic Chemistry Spring 2017 ² MWF 10:20-11:10 AM ² 255 Chemistry Website: Office hours: Immediately following class on W or F, or by appointment TEACHING ASSISTANTS: ~~Xuemei Yang <xuemeiyang@tamu.edu>; 418 Chemistry; Phone # Office hours: Tuesdays 4-5 pm. ~~Pokhraj Ghosh <pokhraj.ghosh@chem.tamu>; 420 Chemistry; Phone # Office hours: Fridays 5-6 pm. UNDERGRADUATE MENTORS: PEER LED TEAM LEARNING (PLTL) LEADERS ZACHARY MARTINEZ MAGY MAURICE MANUEL QUIROZ YICHENG TONG ADMINISTRATIVE ASSISTANT: (All Grade Records and special appointments) Abbey Kunkle darensbourg_asst@chem.tamu.edu; 407 Chemistry; Phone # Office hours: Monday-Friday 8am-5pm WEBPAGE: TEXT: "Inorganic Chemistry", 6th Edition, Shriver & Atkins, W.H. Freeman and Company (ISBN-10: ISBN-13: )

3 CHEM 362 Prof. Marcetta Darensbourg, Rm Phone # Descriptive Inorganic Chemistry Spring 2017 ² MWF 10:20-11:10 AM ² 255 Chemistry COURSE GRADING: SCHEDULE HOUR EXAM 1 15% FEBRUARY 15 HOUR EXAM 2 15% MARCH 29 HOUR EXAM 3 15% APRIL 19 FINAL EXAM 25% MAY 8 PROJECTS 15% QUIZZES: 15% POSTER DAY 1 APRIL 10 POSTER DAY 2 APRIL 12 Projects and the PLTL program: We are participating in the Peer Led Team Learning program. You will have available to you times when you can work on projects (especially the Posters) and also homework/review questions with a former 362 student as PLTL leader. You may choose your outside class time with one of the following: Manuel Quiroz, Zach Martinez, Magy Mekhail, Yicheng Tong. Their scheduled times are Monday Sunday at 5 p.m. The day, the room, and student leader are to be announced. You are expected to select one leader within the team and stick with that team throughout the semester. The main project is the Poster, and each of these Leaders are expert in poster preparation. They will guide you through the process.

4 By way of introducing the applications of Inorganic Chemistry, we will begin today s lecture with two major topics from which the poster projects will be chosen and developed..

6 Metals in Medicine Orvig, Science 300, May 9, 2003

The Scope of Inorganic Chemistry Medicine MRI X-ray contrast imaging drugs (arthri6s, cancer, Biochemistry/Biology metalloproteins metalloenzymes O 2

and electronic structures reactivity Materials Science electrical and magnetic properties of solids solid state structures semiconductors superconductors

7 The Scope of Inorganic Chemistry Medicine MRI X-ray contrast imaging drugs (arthri6s, cancer, Biochemistry/Biology metalloproteins metalloenzymes O 2 binding catalysis ion transport Organic Chemistry organometallics metal compounds in synthesis/catalysis INORGANIC CHEMISTRY new compounds geometrical and electronic structures reactivity Materials Science electrical and magnetic properties of solids solid state structures semiconductors superconductors (high T c ) Geology/Geochemistry synthesis and structure of minerals stellar evolution astrochemistry Organometallic Chemistry new compounds structures catalysis

8 If some universal catastrophe were to engulf the world, and humankind Could retain one scientific concept in order to rebuild civilization, what would that one concept be? Response for physicists (Richard Feynman in Six Easy Pieces ): The modern idea of atoms. Response for chemists: The periodic table The periodic table encapsulates the concept of elements, organizes physical and chemical trends of substances, and compares the structure of the different atoms All in a very small space. Inorganic Chemists think they own the Periodic Table. So, How did it all start?

9 Well, Our whole universe was in a hot, dense state Then nearly fourteen billion years ago expansion started, wait The earth began to cool, the autotrophs began to drool Neanderthals developed tools We built a wall (we built the pyramids) Math, science, history, unraveling the mysteries That all started with the big bang! Hey! Since the dawn of man is really not that long As every galaxy was formed in less time than it takes to sing this song A fraction of a second and the elements were made The bipeds stood up straight, the dinosaurs all met their fate They tried to leap but they were late And they all died (they froze their asses off) The oceans and Pangea, see ya wouldn't wanna be ya Set in motion by the same big bang! It all started with the big bang!

10 The first project: The Elements Stable vs.unstable Isotopes Distribution of Stable Isotopes and Atomic Mass Detection by Mass Spectrometry

11 6 3 Li H 2 4 2He + Energy 8 4 Be with t 1/2 of ca sec

12 Stable vs. Unstable or Fissionable Nuclei Project no. 1. Nuclear Reactions; Web Elements; Mass Spectrometry

13 WebElements TM Periodic Table Group Period 1 1 H 2 He 2 3 Li 4 Be 5 B 6 C 7 N 8 O 9 F 10 Ne 3 11 Na 12 Mg 13 Al 14 Si 15 P 16 S 17 Cl 18 Ar 4 19 K 20 Ca 21 Sc 22 Ti 23 V 24 Cr 25 Mn 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 31 Ga 32 Ge 33 As 34 Se 35 Br 36 Kr 5 37 Rb 38 Sr 39 Y 40 Zr 41 Nb 42 Mo 43 Tc 44 Ru 45 Rh 46 Pd 47 Ag 48 Cd 49 In 50 Sn 51 Sb 52 Te 53 I 54 Xe 6 55 Cs 56 Ba * 71 Lu 72 Hf 73 Ta 74 W 75 Re 76 Os 77 Ir 78 Pt 79 Au 80 Hg 81 Tl 82 Pb 83 Bi 84 Po 85 At 86 Rn 7 87 Fr 88 Ra * * 103 Lr 104 Rf 105 Db 106 Sg 107 Bh 108 Hs 109 Mt 110 Ds 111 Rg 112 Uub 113 Uut 114 Uuq 115 Uup 116 Uuh 117 Uus 118 Uuo *Lanthanoids * 57 La 58 Ce 59 Pr 60 Nd 61 Pm 62 Sm 63 Eu 64 Gd 65 Tb 66 Dy 67 Ho 68 Er 69 Tm 70 Yb **Actinoids * * 89 Ac 90 Th 91 Pa 92 U 93 Np 94 Pu 95 Am 96 Cm 97 Bk 98 Cf 99 Es 100 Fm 101 Md 102 No

14 Mass Spectra computer:

15 Dimitri Mendeleev A Z E Z = No. protons in nucleus, Atomic number A = Mass number; no. of protons + neutrons in nucleus

18 Lecture January 20, 2017 Paradigm Shift: Development of Current Atomic Theory Spectroscopy and Energy Levels in Atoms OR, Show me the Electrons!

19 Color Red Yellow Metal Flame Colors Carmine: Lithium compounds. Masked by barium or sodium. Scarlet or Crimson: Strontium compounds. Masked by barium. Yellow-Red: Calcium compounds. Masked by barium. Sodium compounds, even in trace amounts. A yellow flame is not indicative of sodium unless it persists and is not intensified by addition of 1% NaCl to the dry compound. White White-Green: Zinc Green Blue Violet Emerald: Copper compounds, other than halides. Thallium. Blue-Green: Phosphates, when moistened with H 2 SO 4 or B 2 O 3. Faint Green: Antimony and NH 4 compounds. Yellow-Green: Barium, molybdenum. Azure: Lead, selenium, bismuth, CuCl 2 and other copper compounds moistened with hydrochloric acid. Light Blue: Arsenic and come of its compounds. Greenish Blue: CuBr 2, antimony Potassium compounds other than borates, phosphates, and silicates. Masked by sodium or lithium. Purple-Red: Potassium, rubudium, and/or cesium in the presence of sodium when viewed through a blue glass.

20 Electromagnetic Radiation Spectrum E = hν = h(c/λ)

As the electrons fall from the excited state to the ground state, they emit the energy they absorbed in the form of electromagnetic radiation (heat, light, etc.

21 Atomic Emission (Spectroscopy) An emission spectrum requires first the addition of energy to a material. The addition of energy promotes electrons of that material from the ground state to an excited state. As the electrons fall from the excited state to the ground state, they emit the energy they absorbed in the form of electromagnetic radiation (heat, light, etc.) Applications Atomic emission is used in street lamps, fluorescent lights, and neon signs. Two common street lamps using this are the mercury lamp and the sodium lamp. Neon signs frequently implement the emission spectra of other gases such as argon and krypton. Very sophisticated instrumental techniques such as flame photometry and atomic absorption are broadly based on the principles of atomic emission.

22 Continuous and Line Spectra Dark Side of the Moon Pink Floyd

23 In the news: January 20, 2016: Infer what we cannot see...

24 Sun Emission Spectra Hydrogen Helium Mercury Uranium 700 nm 600 nm 500 nm 400 nm

What does it all mean? A Bit of History A Z E Z = No.

26 Marie Curie

27 So how to connect the physical properties of elements to the Periodic Table? Physicists! The current model of the atom belongs to Physicists! Hund DeBroglie Planck Schrodinger Einstein Heisenberg Bohr Pauli

28 Niels Bohr and wife Margrethe around 1930 Taken from John L. Heilbron s History: The Path to the quantum Atom, Nature 498, 27-30, (06 June 2013)

Taken from John L. Heilbron s History: The Path to the quantum Atom, Nature 498, 27-30, (06 June 2013) To develop his model, Bohr followed an analogy to the radiation theory of Max Planck (right).

29 Taken from John L. Heilbron s History: The Path to the quantum Atom, Nature 498, 27-30, (06 June 2013) To develop his model, Bohr followed an analogy to the radiation theory of Max Planck (right).... Bohr had developed a doctrine of multiple partial truths, each of which contained some bit of reality, and all of which together might exhaust it. There exist so many different truths I can almost call it my religion that I think that everything that is of value is true.

30 Uranium Mercury Helium Hydrogen Sun 700nm 600nm 500nm 400nm Emission Spectra Niels Bohr and Albert Einstein, 1925 Taken from John L. Heilbron s History: The Path to the quantum Atom, Nature 498, 27-30, (06 June 2013)

31 The Bohr Atom: electrons in concentric rings The Balmer formula expresses the frequencies of some lines in the spectrum of hydrogen in simple algebra: ν n = R(1/2 2 1/n 2 ) where ν n is the nth Balmer line and R is the universal Rydberg constant for frequency, named in honour of the Swedish spectroscopist Johannes Rydberg, who generalized Balmer s formula to apply to elements beyond hydrogen. Taken from John L. Heilbron s History: The Path to the quantum Atom, Nature 498, 27-30, (06 June 2013) Each level can accommodate 2 n 2 electron: Periodic Table Rows

The Hydrogen Atom Spectrum and Energy Levels Energy 0-1/16 R H

transitions shown) Quantum Number n 5 4 3 2 + Lyman Series

the atom Circular motion (classic physics) used to explain

32 The Hydrogen Atom Spectrum and Energy Levels Energy 0-1/16 R H -1/9 R H -1/4 R H Paschen Series (IR) Balmer Series (visible transitions shown) Quantum Number n Lyman Series (UV) ν n = R(1/n final 2 1/n initial2 ) Niels Bohr s view of the atom Circular motion (classic physics) used to explain behavior of electron Hydrogen -R H

33 Energy 0-1/16 R H -1/9 R H -1/4 R H Quantum Number n 5 4 Paschen Series (IR) 3 Balmer Series (visible transitions shown) 2 For Hydrogen: E = -R H n 2 Rydberg constant for hydrogen,r H R H = m e e 4 = 2.179x10-18 J 8 ε o2 h 2 = 13.6 ev Lyman Series (UV) General equation for Rydberg constant for any element R = -m Z 2 e 4 8 ε o 2 h 2 -R H 1 Note: The predicted emission spectra using the Rydberg constant was only successful for simple elements such as H and failed for heavier atoms due to the limitations of the Bohr view of the atom. This led to the foundations of quantum mechanics.

34 Inorganic Chemistry Chapter 1: Figure 1.5 Properties of waves: Addition for reinforcement or cancellation 2009 W.H. Freeman

Properties of waves: Squared = amplitude Boundaries => Restrictions on values a node

36 Inorganic Chemistry Chapter 1: Figure 1.4 Time-independent Schrödinger equation (general one dimension) E ψ = H ψ a node Need both radial and angular functions 2009 W.H. Freeman

37 Need both radial and angular functions Both radial and angular functions have nodes

38 Nodes, (not toads) Summary: Total # Nodes = n - 1 # Radial Nodes = n - l - 1 # Angular Nodes = l Where n = principal quantum number; l = angular momentum quantum number

39 Summarizing: Solutions Required Quantum Numbers

40 Quantum Numbers n is the principal quantum number, indicates the size of the orbital, has all positive integer values of 1 to (infinity) l is the angular momentum quantum number, represents the shape of the orbital, has integer values of (n 1) to 0; l = no. angular nodes m l is the magnetic quantum number, represents the spatial direction of the orbital, can have integer values of -l to 0 to l m s is the spin quantum number, has little connection to directionality, can have values of either +1/2 or -1/2 l (angular momentum) orbital 0 s 1 p 2 d 3 f Other terms: electron configuration, noble gas configuration, valence shell Pauli Exclusion principle: no two electrons can have all four of the same quantum numbers in the same atom (Every electron has a unique set.) Hund s Rule: when electrons are placed in a set of degenerate orbitals, the ground state has as many electrons as possible in different orbitals, and with parallel spin. Aufbau (Building Up) Principle: the ground state electron configuration of an atom can be found by putting electrons in orbitals, starting with the lowest energy and moving progressively to higher energy.

41 Where are the Electrons?? Assignments In atoms are guided by Pauli Exclusion Principle: No two electrons can have the same set of 4 quantum numbers. Hund s Rule: Electrons go into degenerate orbitals with spins aligned until forced to pair up.

42 Inorganic Chemistry Chapter 1: Figure 1.7 Box Diagrams 2009 W.H. Freeman

43 Quantum Numbers n is the principal quantum number, indicates the size of the orbital, has all positive integer values of 1 to (infinity) l is the angular momentum quantum number, represents the shape of the orbital, has integer values of n-1 to 0 m l is the magnetic quantum number, represents the spatial direction of the orbital, can have integer values of -l to 0 to l m s is the spin quantum number, has little physical meaning, can have values of either +1/2 or -1/2 l (angular momentum) orbital 0 s 1 p 2 d 3 f Other terms: electron configuration, noble gas configuration, valence shell Pauli Exclusion principle: no two electrons can have all four of the same quantum numbers in the same atom Hund s Rule: when electrons are placed in a set of degenerate orbitals, the ground state has as many electrons as possible in different orbitals, and with parallel spin. Aufbau (Building Up) Principle: the ground state electron configuration of an atom can be found by putting electrons in orbitals, starting with the lowest energy and moving progressively to higher energy.

(phases) of the wavefunction either side of the nucleus

46 Orbitals and Shapes/Electron Distribution The p-orbitals Each p-orbital has two lobes with positive and negative values (phases) of the wavefunction either side of the nucleus separated by a nodal plane where the wavefunction is zero. The s-orbital

# Angular Nodes = l # Radial Nodes = n - l - 1 Summary: # Radial Nodes = n - l - 1 # Angular

48 Where are the nodes in orbitals??? (MFT, Figure 2.8 shows both radial and angular) Cl, 3s C, 2p z Cl, 3p z Ti 3+, 3d z 2 Ti 3+, 3d x 2 -y 2 Ti 3+, 3d x 2 -y 2 Copyright 2014 Pearson Education, Inc. Note the orientation of the viewer: down z or x or y axes

49 Two angular nodes

51 The f-orbitals

52 Interpretation of orbital images ψ2px ψ22px

53 Interpretation of orbital images ψ3dz2 ψ23dz2

54 Interpretation of orbital images ψ3pz ψ23pz

55 Quantum Numbers n is the principal quantum number, indicates the size of the orbital, has all positive integer values of 1 to (infinity) l is the angular momentum quantum number, represents the shape of the orbital, has integer values of n-1 to 0 m l is the magnetic quantum number, represents the spatial direction of the orbital, can have integer values of -l to 0 to l m s is the spin quantum number, has little physical meaning, can have values of either +1/2 or -1/2 l (angular momentum) orbital 0 s 1 p 2 d 3 f Other terms: electron configuration, noble gas configuration, valence shell Pauli Exclusion principle: no two electrons can have all four of the same quantum numbers in the same atom Hund s Rule: when electrons are placed in a set of degenerate orbitals, the ground state has as many electrons as possible in different orbitals, and with parallel spin. Aufbau (Building Up) Principle: the ground state electron configuration of an atom can be found by putting electrons in orbitals, starting with the lowest energy and moving progressively to higher energy.

56 I d like to make two points:

57 2p 3p 3d

58 Energy Levels for Electron Configurations The Aufbau Principle The Pauli Exclusion Principle Hund s Rules

59 While n is the principal energy level, the l value also has an effect

60 Screening: The 4s electron penetrates Inner shell electrons more efficiently than does 3d in neutral atoms. Reverses in positive ions.

61 How to handle atoms larger than H? Effective Nuclear Charge or Z eff

62 H-atom Orbital Sizes Increase with n r 2 Ψ 2 Electron probability 1s most probable distance: a 0 = Bohr radius = 53 pm Distance from nucleus

63 How Gravity Works (in the Newtonian sense)

64 How Screening Works Example Li + + e -

65 Slater s Rules for Calculating Z eff 1) Write the electron configuration for the atom as follows: (1s)(2s,2p)(3s,3p) (3d) (4s,4p) (4d) (4f) (5s,5p) 2) Any electrons to the right of the electron of interest contributes no shielding. (Approximately correct statement.) 3) All other electrons in the same group as the electron of interest shield to an extent of 0.35 nuclear charge units 4) If the electron of interest is an s or p electron: All electrons with one less value of the principal quantum number shield to an extent of 0.85 units of nuclear charge. All electrons with two less values of the principal quantum number shield to an extent of 1.00 units. 5) If the electron of interest is an d or f electron: All electrons to the left shield to an extent of 1.00 units of nuclear charge. 6) Sum the shielding amounts from steps 2-5 and subtract from the nuclear charge value to obtain the effective nuclear charge.

66 Slater s Rules: Examples Calculate Z eff for a valence electron in fluorine. (1s 2 )(2s 2,2p 5 ) Rule 2 does not apply; therefore, for a valence electron the shielding or screening is (0.35 6) + (0.85 2) = 3.8 Z eff = = 5.2 for a valence electron. Calculate Z eff for a 6s electron in Platinum. (1s 2 )(2s 2,2p 6 )(3s 2,3p 6 ) (3d 10 ) (4s 2,4p 6 ) (4d 10 ) (4f 14 ) (5s 2,5p 6 ) (5d 8 ) (6s 2 ) Rule 2 does not apply, and the shielding is: (0.35 1) + ( ) + ( ) = Z eff = = 4.15 for a valence electron.

67 Inorganic Chemistry Chapter 1: Table W.H. Freeman

68 H-atom Orbital Sizes Increase with n r 2 Ψ 2 Radial distribution probability 1s most probable distance: a 0 = Bohr radius = 53 pm Distance from nucleus Hydrogenic orbitals

69 All the s orbitals of Cs The shell structure of many-e atoms is enormously accentuated by screening. Vertical scale in next plot

70 All the s orbitals of Cs The shell structure of many-e atoms is enormously accentuated by screening. Horizontal scale in previous plot

71 The Periodic Table Special Names Group 1: Alkali Metals Group 2: Alkaline-earth metals Group 16: Chalcogens Group 17: Halogens Group 18: Noble gases watch?v=smwlzwgmmwc

72 Three types of Magnetic Behavior Paramagnetism: atoms, molecules, and solids with unpaired electrons are attracted in a magnetic field Diamagnetic: substances with no unpaired electrons which are weakly repelled in a magnetic field Ferro-magnetism: the unpaired electons are aligned with their neighbors even in the absence of a magnetic field Magnetic domains: the groups of mutually aligned spins in a ferromagnetic substance Ferro-magnet In the absence of a magnetic field Ferro-magnet In the presence of a magnetic field

73 Figure 1.4 The possible sets of quantum numbers for n = 1 and n = 2.

74 Summary of Electronic Energy Scales - The Hierarchical Approach The largest energy level splittings in atoms and molecules are due to principal quantum number changes (and concomitant differences in screening). This underlies our familiar focus on valence vs. core-levels. Energy level splittings between different l levels (e.g., between s, p, d electrons) are often comparable to bonding effects evident in both the concept of hybrid orbitals and in mixed orbital parentage of molecular orbitals. In T.M. complexes, e -e repulsion differences are often comparable to M-L bonding energies. A big part of ligand-field theory deals with the complications that arise from the competition between these energetic effects.

75 Carbon: Atomic Energy Levels Experimental atomic energy levels (cm 1 ). sp 3 s 2 p 2 28,906 Hybridization cost! 5 S 1 S 1 D 10,163 3 P e -e repulsion differences? Where do these energy levels come from?

76 Ti 2+ ion energy levels Again, where are all the energy levels coming from? Hint: They are all [Ar]3d 2, the lowest [Ar]3d 1 4s 1 energy levels are at ~38,000 cm 1

Paradigm Shift: Development of Current Atomic Theory Spectroscopy and Energy Levels in Atoms. OR, Show me the Electrons!

Lecture 2 362 January 16, 2019 Paradigm Shift: Development of Current Atomic Theory Spectroscopy and Energy Levels in Atoms OR, Show me the Electrons! Color Red Yellow White Green Blue Violet Metal Flame