The Free Atom. Electronegativity for carbon: 2.5 Electronegativity for hydrogen: 2.2. Atomic energy levels, valence orbital ionization energies (VOIE)

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2 The Free Atom Atomic energy levels, valence orbital ionization energies (VOIE) Electronegativity for carbon: 2.5 Electronegativity for hydrogen: 2.2

3 The Free Atom Atomic energy levels, valence orbital ionization energies (VOIE) Electronegativity for carbon: 2.5 Electronegativity for hydrogen: 2.2

4 The Free Atom Atomic energy levels, valence orbital ionization energies (VOIE) Electronegativity for carbon: 2.5 Electronegativity for hydrogen: 2.2

5 The Free Atom Atomic energy levels, valence orbital ionization energies (VOIE) Quartet ground state, spin multiplicity given by 2S + 1 = 2( 3 2 ) + 1 = 4 Four possible values for the spin: + 3 2, + 1 2, 1 2, 3 2

6 The Free Atom Atomic energy levels, valence orbital ionization energies (VOIE) Quartet ground state, spin multiplicity given by 2S + 1 = 2( 3 2 ) + 1 = 4 Four possible values for the spin: + 3 2, + 1 2, 1 2, 3 2

7 The Free Atom Atomic energy levels, valence orbital ionization energies (VOIE) Quartet ground state, spin multiplicity given by 2S + 1 = 2( 3 2 ) + 1 = 4 Four possible values for the spin: + 3 2, + 1 2, 1 2, 3 2

8 Single versus Triple Bonds Atomic energy levels, valence orbital ionization energies (VOIE) Hf Hf for P 2 is +144 kj/mol for P N is +104 kj/mol

9 Single versus Triple Bonds Atomic energy levels, valence orbital ionization energies (VOIE) Hf Hf for P 2 is +144 kj/mol for P N is +104 kj/mol

10 Single versus Triple Bonds Atomic energy levels, valence orbital ionization energies (VOIE) Hf Hf for P 2 is +144 kj/mol for P N is +104 kj/mol

11 Multiple Bonds in Inorganic Chemistry Discarding the double bond rule? DOI: /anie The higher the sum of electronegativities of the two atoms involved in bonding, the higher the probability for formation of a double bond The value 5.0 is given as an approximate limit The use of bulky ligands has allowed the synthesis of compounds containing Si=Si (ΣEN = 3.6) or P=P (ΣEN = 4.2) double bonds

12 Multiple Bonds in Inorganic Chemistry Discarding the double bond rule? DOI: /anie The higher the sum of electronegativities of the two atoms involved in bonding, the higher the probability for formation of a double bond The value 5.0 is given as an approximate limit The use of bulky ligands has allowed the synthesis of compounds containing Si=Si (ΣEN = 3.6) or P=P (ΣEN = 4.2) double bonds

13 Multiple Bonds in Inorganic Chemistry Discarding the double bond rule? DOI: /anie The higher the sum of electronegativities of the two atoms involved in bonding, the higher the probability for formation of a double bond The value 5.0 is given as an approximate limit The use of bulky ligands has allowed the synthesis of compounds containing Si=Si (ΣEN = 3.6) or P=P (ΣEN = 4.2) double bonds

14 Multiple Bonds in Inorganic Chemistry Discarding the double bond rule? DOI: /anie The higher the sum of electronegativities of the two atoms involved in bonding, the higher the probability for formation of a double bond The value 5.0 is given as an approximate limit The use of bulky ligands has allowed the synthesis of compounds containing Si=Si (ΣEN = 3.6) or P=P (ΣEN = 4.2) double bonds

15 Yoshifuji s Example of a Phosphobenzene Isolated and characterized in 1981, DOI: /ja00405a054 Replacement of even one ortho tert-butyl group with isopropyl leads to polymerization Comparison is to azobenzene, Ph-N=N-Ph, a perfectly stable compound

16 Yoshifuji s Example of a Phosphobenzene Isolated and characterized in 1981, DOI: /ja00405a054 Replacement of even one ortho tert-butyl group with isopropyl leads to polymerization Comparison is to azobenzene, Ph-N=N-Ph, a perfectly stable compound

Yoshifuji s Example of a Phosphobenzene Isolated and characterized in 1981, DOI: 10.

17 Yoshifuji s Example of a Phosphobenzene Isolated and characterized in 1981, DOI: /ja00405a054 Replacement of even one ortho tert-butyl group with isopropyl leads to polymerization Comparison is to azobenzene, Ph-N=N-Ph, a perfectly stable compound

18 Structure: NH 3 versus PH 3 Easier mixing/hybridization of valence atomic s and p orbitals for N versus P Valence atomic s and p orbitals are closer in energy for N than for P

19 Structure: NH 3 versus PH 3 Easier mixing/hybridization of valence atomic s and p orbitals for N versus P Valence atomic s and p orbitals are closer in energy for N than for P

20 Structure: NH 3 versus PH 3 Easier mixing/hybridization of valence atomic s and p orbitals for N versus P Valence atomic s and p orbitals are closer in energy for N than for P

21 The Free Atom Atomic energy levels, valence orbital ionization energies (VOIE) Electronegativity for carbon: 2.5 Electronegativity for hydrogen: 2.2

22 The Free Atom Atomic energy levels, valence orbital ionization energies (VOIE) Electronegativity for carbon: 2.5 Electronegativity for hydrogen: 2.2

23 The Free Atom Atomic energy levels, valence orbital ionization energies (VOIE) Electronegativity for carbon: 2.5 Electronegativity for hydrogen: 2.2

24 Structure: NH 3 versus PH 3 Ammonia lone pair is 25%s, 75%p; this is ideal sp 3 hybridization

25 Structure: NH 3 versus PH 3 Ammonia lone pair is 25%s, 75%p; this is ideal sp 3 hybridization

26 Structure: NH 3 versus PH 3 Ammonia lone pair is 54%s, 46%p; this is sp 0.84 hybridization

27 Structure: NH 3 versus PH 3 Ammonia lone pair is 54%s, 46%p; this is sp 0.84 hybridization

28 Inversion Frequency NH 3 vs. PH 3 Ammonia inversion involves an umbrella motion of the atoms Inversion frequency greater by factor of 4000 for NH 3! 155 vs kj/mol inversion barrier

29 Inversion Frequency NH 3 vs. PH 3 Ammonia inversion involves an umbrella motion of the atoms Inversion frequency greater by factor of 4000 for NH 3! 155 vs kj/mol inversion barrier

30 Inversion Frequency NH 3 vs. PH 3 Ammonia inversion involves an umbrella motion of the atoms Inversion frequency greater by factor of 4000 for NH 3! 155 vs kj/mol inversion barrier

31 Inversion Frequency NH 3 vs. PH 3 Ammonia inversion involves an umbrella motion of the atoms Lone pair has to become pure p at the transition state for inversion Inversion reaction coordinate corresponds to an A 1 normal mode of vibration

32 Inversion Frequency NH 3 vs. PH 3 Ammonia inversion involves an umbrella motion of the atoms Lone pair has to become pure p at the transition state for inversion Inversion reaction coordinate corresponds to an A 1 normal mode of vibration

33 Inversion Frequency NH 3 vs. PH 3 Ammonia inversion involves an umbrella motion of the atoms Lone pair has to become pure p at the transition state for inversion Inversion reaction coordinate corresponds to an A 1 normal mode of vibration

34 Bent s Rule DOI: /ed037p616 Distribution of atomic s character in molecules and its chemical implications s character accumulates in orbitals directed toward electropositive substituents A lone pair is like a bond to a group of infinite electropositivity Properties of inversion barrier: increases with increasing relative substituent EN Example: trisilylamine is planar at nitrogen

35 Bent s Rule DOI: /ed037p616 Distribution of atomic s character in molecules and its chemical implications s character accumulates in orbitals directed toward electropositive substituents A lone pair is like a bond to a group of infinite electropositivity Properties of inversion barrier: increases with increasing relative substituent EN Example: trisilylamine is planar at nitrogen

36 Bent s Rule DOI: /ed037p616 Distribution of atomic s character in molecules and its chemical implications s character accumulates in orbitals directed toward electropositive substituents A lone pair is like a bond to a group of infinite electropositivity Properties of inversion barrier: increases with increasing relative substituent EN Example: trisilylamine is planar at nitrogen

37 Bent s Rule DOI: /ed037p616 Distribution of atomic s character in molecules and its chemical implications s character accumulates in orbitals directed toward electropositive substituents A lone pair is like a bond to a group of infinite electropositivity Properties of inversion barrier: increases with increasing relative substituent EN Example: trisilylamine is planar at nitrogen

38 Bent s Rule DOI: /ed037p616 Distribution of atomic s character in molecules and its chemical implications s character accumulates in orbitals directed toward electropositive substituents A lone pair is like a bond to a group of infinite electropositivity Properties of inversion barrier: increases with increasing relative substituent EN Example: trisilylamine is planar at nitrogen

39 Bent s Rule DOI: /ed037p616 Distribution of atomic s character in molecules and its chemical implications s character accumulates in orbitals directed toward electropositive substituents A lone pair is like a bond to a group of infinite electropositivity Properties of inversion barrier: increases with increasing relative substituent EN Example: trisilylamine is planar at nitrogen

40 Explaining the Walsh-Bent Rule Distribution of atomic s character in molecules and its chemical implications

41 s Character and Base Strength Distribution of atomic s character in molecules and its chemical implications N 2 is less basic than pyridine Pyridine is less basic than ammonia The lone pair in these compounds: sp, sp 2, sp 3 As the s character increases, the base strength decreases

42 s Character and Base Strength Distribution of atomic s character in molecules and its chemical implications N 2 is less basic than pyridine Pyridine is less basic than ammonia The lone pair in these compounds: sp, sp 2, sp 3 As the s character increases, the base strength decreases

43 s Character and Base Strength Distribution of atomic s character in molecules and its chemical implications N 2 is less basic than pyridine Pyridine is less basic than ammonia The lone pair in these compounds: sp, sp 2, sp 3 As the s character increases, the base strength decreases

44 s Character and Base Strength Distribution of atomic s character in molecules and its chemical implications N 2 is less basic than pyridine Pyridine is less basic than ammonia The lone pair in these compounds: sp, sp 2, sp 3 As the s character increases, the base strength decreases

45 s Character and Base Strength Distribution of atomic s character in molecules and its chemical implications N 2 is less basic than pyridine Pyridine is less basic than ammonia The lone pair in these compounds: sp, sp 2, sp 3 As the s character increases, the base strength decreases

46 Nitric Acid Synthesis Commercialization relied upon large scale NH 3 availability via Haber-Bosch Largest use is for ammonium nitrate fertilizer production

47 Nitric Acid Synthesis Commercialization relied upon large scale NH 3 availability via Haber-Bosch Largest use is for ammonium nitrate fertilizer production

48 Nitric Acid Synthesis Commercialization relied upon large scale NH 3 availability via Haber-Bosch Largest use is for ammonium nitrate fertilizer production

49 Nitric Acid Synthesis Depends upon catalyst selectivity for NO over other thermodynamically favorable products

50 Nitric Acid Synthesis Depends upon catalyst selectivity for NO over other thermodynamically favorable products

51 Nitrate versus Metaphosphate Nitrate ion has D 3h symmetry (isoelectronic to BF 3 ) Nitrate enjoys delocalized π bonding Metaphosphate is not seen as a monomer, but rather forms rings Opening metaphosphate rings gives chains such as is found in ATP

52 Nitrate versus Metaphosphate Nitrate ion has D 3h symmetry (isoelectronic to BF 3 ) Nitrate enjoys delocalized π bonding Metaphosphate is not seen as a monomer, but rather forms rings Opening metaphosphate rings gives chains such as is found in ATP

53 Nitrate versus Metaphosphate Nitrate ion has D 3h symmetry (isoelectronic to BF 3 ) Nitrate enjoys delocalized π bonding Metaphosphate is not seen as a monomer, but rather forms rings Opening metaphosphate rings gives chains such as is found in ATP

54 Nitrate versus Metaphosphate Nitrate ion has D 3h symmetry (isoelectronic to BF 3 ) Nitrate enjoys delocalized π bonding Metaphosphate is not seen as a monomer, but rather forms rings Opening metaphosphate rings gives chains such as is found in ATP

55 Nitrate versus Metaphosphate Nitrate ion has D 3h symmetry (isoelectronic to BF 3 ) Nitrate enjoys delocalized π bonding Metaphosphate is not seen as a monomer, but rather forms rings Opening metaphosphate rings gives chains such as is found in ATP

56 Dihydrogen Tetrametaphosphate pka = (MeCN, 23 o C)

57 Tetrametaphosphate Anhydride O P O O O P O P O O H H O P O O O (PPN + ) 2 O 1 equiv. DCC MeCN 23 o C, 30 min H 2 O 82% acetone (< 0.5 w/w H 2 O) 23 o C, 1 min > 99% (in situ) DCC = N,N'-dicyclohexylcarbodiimide O O P O O O O P O P O O (PPN + ) 2 O P O 31 P{ 1 H} NMR (CD 3 CN) A-2P P 4 O 11 A 2 X 2 spin system X-2P H 3PO 4 aq. DCC molten N O N O P O O O O O P P O P O O O O 3/5 H 2O nbu 3N N O N P 4O 10 Glonek, T.; Myers, T. C.; Han, J. R. J. Am. Chem. Soc. 1970, 92, Glonek, T.; Van Wazer, J. R.; Kleps, R. A.; Myers, T. C. Inorg. Chem. 1974, 13,

58 Phosphorus Pentoxide, P 4 O 10 A nice inorganic example of T d symmetry!

59 Phosphorus Pentoxide, P 4 O 10 A nice inorganic example of T d symmetry!

60 Nitric Oxide Science, 1992, 258,

61 Other Oxides of Nitrogen Nitrous oxide, N 2 O, is known as laughing gas N 4 O isolated in 1993 as a pale yellow solid NO 2 is a brown paramagnetic gas that dimerizes reversibly Nitrite is the [NO 2 ] anion Nitrate is the [NO 3 ] anion

62 Other Oxides of Nitrogen Nitrous oxide, N 2 O, is known as laughing gas N 4 O isolated in 1993 as a pale yellow solid NO 2 is a brown paramagnetic gas that dimerizes reversibly Nitrite is the [NO 2 ] anion Nitrate is the [NO 3 ] anion

63 Other Oxides of Nitrogen Nitrous oxide, N 2 O, is known as laughing gas N 4 O isolated in 1993 as a pale yellow solid NO 2 is a brown paramagnetic gas that dimerizes reversibly Nitrite is the [NO 2 ] anion Nitrate is the [NO 3 ] anion

64 Other Oxides of Nitrogen Nitrous oxide, N 2 O, is known as laughing gas N 4 O isolated in 1993 as a pale yellow solid NO 2 is a brown paramagnetic gas that dimerizes reversibly Nitrite is the [NO 2 ] anion Nitrate is the [NO 3 ] anion

65 Other Oxides of Nitrogen Nitrous oxide, N 2 O, is known as laughing gas N 4 O isolated in 1993 as a pale yellow solid NO 2 is a brown paramagnetic gas that dimerizes reversibly Nitrite is the [NO 2 ] anion Nitrate is the [NO 3 ] anion

66 The Variety of Nitrogen Oxides

67 Molecular Structure of Hydrazoic Acid Hydrogen-bonded tetramers in nearly planar layers DOI: /ja The crystalline acid is 97.7 wt % nitrogen!

68 Molecular Structure of Hydrazoic Acid Hydrogen-bonded tetramers in nearly planar layers DOI: /ja The crystalline acid is 97.7 wt % nitrogen!

69 Molecular Structure of Hydrazoic Acid Hydrogen-bonded tetramers in nearly planar layers DOI: /ja For the structure determination, single crystals were grown in situ in the X-ray capillary... near the melting point of HN 3 at ca. 193 K in several melting and crystallizing cycles The tip of a finger, carefully touching the capillary, was used as the heating source

70 Molecular Structure of Hydrazoic Acid Hydrogen-bonded tetramers in nearly planar layers DOI: /ja For the structure determination, single crystals were grown in situ in the X-ray capillary... near the melting point of HN 3 at ca. 193 K in several melting and crystallizing cycles The tip of a finger, carefully touching the capillary, was used as the heating source

71 Molecular Structure of Hydrazoic Acid Hydrogen-bonded tetramers in nearly planar layers DOI: /ja For the structure determination, single crystals were grown in situ in the X-ray capillary... near the melting point of HN 3 at ca. 193 K in several melting and crystallizing cycles The tip of a finger, carefully touching the capillary, was used as the heating source

72 Phosphate Rock Mining: Peak Phosphorus

73 Phosphate Rock Reserves Neset2012,

74 Phosphate Rock Reserves

75 Global Sources of Phosphorus Fertilizers Cordell2009,

76 Phosphate Mining in Morocco

77 Cargill Phosphate Mines in Florida

78 Central Florida Mined Out

79 Phosphorus Flow in Africa Cordell2009,

80 Reuse of Human Excreta Cordell2009,

81 Composting to Recycle Human Excreta Composting saves water and energy as well as nitrogen and phosphorus!

82 Changes in Soil Phosphorus Availability with Time Note that phosphorus is continually lost from the system; from Filippelli2008 DOI: /GSELEMENTS

83 Phosphorus Recycling Steve Safferman of MSU pursuing iron-based precipitation scheme

84 Enviropig, U. of Guelph Genetically engineered pig breaks down and absorbs more phosphorus, excretes less

Groups elements. Trends in atomization energies

Groups elements. Trends in atomization energies Groups 15-17 elements CHEM 102 T. Hughbanks Trends in atomization energies Explanation? Group 15 Elements Range from electronegative nitrogen to somewhat electropositive Bi Atomic configurations ns 2 np