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6.5: Ionization Energies

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    371715
    • John Moore, Jia Zhou, and Etienne Garand
    • University of Wisconsin

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    Ionization Energies

    John Moore, Jia Zhou, and Etienne Garand

    Ionization Energy

    Atom Atomic No. IE1 (kJ/mol) IE2 (kJ/mol) IE3 (kJ/mol) IE4 (kJ/mol) IE5 (kJ/mol) IE6 (kJ/mol) IE7 (kJ/mol) IE8 (kJ/mol) IE9 (kJ/mol) IE10 (kJ/mol) IE11 (kJ/mol) IE12 (kJ/mol) IE13 (kJ/mol) IE14 (kJ/mol) IE15 (kJ/mol) IE16 (kJ/mol) IE17 (kJ/mol) IE18 (kJ/mol) IE19 (kJ/mol)
    Atom
    Atomic No.
    IE1 (kJ/mol)
    IE2 (kJ/mol)
    IE3 (kJ/mol)
    IE4 (kJ/mol)
    IE5 (kJ/mol)
    IE6 (kJ/mol)
    IE7 (kJ/mol)
    IE8 (kJ/mol)
    IE9 (kJ/mol)
    IE10 (kJ/mol)
    IE11 (kJ/mol)
    IE12 (kJ/mol)
    IE13 (kJ/mol)
    IE14 (kJ/mol)
    IE15 (kJ/mol)
    IE16 (kJ/mol)
    IE17 (kJ/mol)
    IE18 (kJ/mol)
    IE19 (kJ/mol)
    C. E. Moore, Ionization Potentials and Limits Derived from the Analyses of Optical Spectra, NSRDS-NBS 34, National Bureau of Standards, Washington, DC, 1970.
    For elements 57-72, values were obtained from Martin, W. C.; Hagan, Lucy; Reader, Joseph; Sugar, Jack J. Phys. Chem. Ref. Data, 1974, 3, 771-779.
    For elements 59-73, fifth IEs came from Sugar, Jack J. Opt. Soc. Am. 1975, 65, 1366-1367.
    For Lr see C&EN, Volume 93 Issue 15 | p. 8 | News of The Week, Issue Date: April 13, 2015 | Web Date: April 9, 2015 Lawrencium Ionization Energy Measured.
    *Values for La, Hf, and Lr have been overwritten with more recent data
    H 1 1311.7                                    
    He 2 2371.6 5248.8                                  
    Li 3 520.1 7296.1 11811.7                                
    Be 4 899.2 1756.6 14844.3 21000.7                              
    B 5 800.4 2426.5 3658.7 25018.5 32817.3                            
    C 6 1086.8 2351.9 4618.2 6221.0 37820.9 47262.4                          
    N 7 1402.9 2856.4 4575.9 7472.8 9442.3 53252.7 64339.3                        
    O 8 1313.6 3391.1 5300.3 7467.4 10987.1 13322.7 71313.7 84050.3                      
    F 9 1681.0 3375.1 6050.4 8416.4 11020.0 15159.5 17863.2 92008.4                      
    Ne 10 2080.1 3962.7 6175.1 9374.5 12195.7 15236.0                          
    Na 11 495.7 4562.8 6913.2 9540.5 13372.9 16630.2 20111.8 25487.1 28924.4                    
    Mg 12 737.5 1450.2 7730.4 10544.9 13626.6 18029.3 21739.1 25661.0 31637.5 35444.9 169932.9                
    Al 13 577.4 1816.1 2744.0 11574.4 14836.6 18372.7 23342.7 27510.9 31849.8 38449.4 42636.9 201216.3              
    Si 14 786.3 1576.6 3228.4 4354.4 16087.0 19790.1 23775.0 29319.0 33946.4 38719.6 45927.0 50481.1              
    P 15 1011.8 1895.9 2909.6 4954.9 6272.2 21266.7 25405.6 29839.1 35952.4 41050.7 46255.1 54060.7 58996.0            
    S 16 999.3 2257.8 3377.0 4562.8 6995.2 8493.5 27111.4 31724.4 36563.1 43244.7                  
    Cl 17 1255.3 2296.4 3849.8 5162.0 6541.7 9330.1 11025.4 33605.8 38661.7 43929.8                  
    Ar 18 1520.1 2664.9 3946.3 5768.9 7236.4 8809.1 11964.2 13841.8 40620.3                    
    K 19 418.6 3069.2 4438.3 5876.0 7975 9619.6 11385.3 14955.2 16975.6 48609.3                  
    Ca 20 589.6 1145.3 4941.0 6464.5 8142.4 10496 12350.1 14183.3 18139.2 20386.4 57100.0 63197.9              
    Sc 21 632.9 1243.7 2388.0 7130.3 8876.7 10719.5 13314 15341.2 17367.4 21757.4 24098.2 66246.8              
    Ti 22 659.0 1315.1 2715.1 4172.0 9629.2 11578.2 13585.1   18621.7   25665.1 28122.6 76069.0            
    V 23 650.3 1370.1 2865.6 4631.3 6290.8 12437.0 14569.3 16759.5       29814.0 32447.1 86557.0          
    Cr 24 652.5 1591.0 2986.2 4785.7 7043.4 8741.6 15543.8 17849.8 20223.3       34252.3 37069.7 97739.6        
    Mn 25 717.1 1509.0 3250.6   7332.9   11504.9 18911.1 21419.7 23928.4       38980.1 41971.1 109597.7      
    Fe 26 762.2 1561.1 2956.3         14569.3 22674.1 25279.2 27980.7   34252.3 37629.3 44093.8 47181.3 122150.4    
    Co 27 758.4 1645.1 3231.3           29428.0             49400.5 52777.5 135368.9  
    Ni 28 736.5 1751.2 3488.9                 33769.9     43900.8     58566.6  
    Cu 29 745.3 1957.7 3553.6                               64741.7
    Zn 30 906.1 1732.9 3830.5                                
    Ga 31 578.9 1981.8 2962.1 6194.4 8299 10874 13585                        
    Ge 32 760.3 1537.0 3300.8 4409.4 9011.7 11183 13981                        
    As 33 946.5 1949.0 2730.5 4833.9 6040.0 12301.9 14183                        
    Se 34 940.7 2074.4 3087.5 4139.2 7053.1 7882.9 14955.2                        
    Br 35 1142.4 2084.1 3463.8         18621.7                      
    Kr 36 1350.4 2369.7 3560.3                                
    Rb 37 402.9 2653.3 3859.4             26726.4                  
    Sr 38 549.2 1063.9 0.0 5499.7   31261.3                          
    Y 39 627.2 1196.4 3762.9   7429.4   36085.5                        
    Zr 40 670.6 1353.7 2392.8 3277.6   9552.0                          
    Nb 41 653.2 1350.8 2711.2 3695.4 4824.3 9938.0 12060.7                        
    Mo 42 685.0 1558.2 2617.6 4476.9 5904.9 6561.0 12157.2 14762.3                      
    Tc 43 702.4 1472.4 0.0                                
    Ru 44 710.5 1617.1 2746.0                                
    Rh 45 719.8 1743.5 2995.9                                
    Pd 46 803.7 1873.7 3176.3                                
    Ag 47 730.8 2072.5 3359.6                                
    Cd 48 867.5 1631.0 3615.3                                
    In 49 558.2 1819.7 2704.5 5248.8                              
    Sn 50 708.4 1411.4 2941.8 3928.9 6975.9                            
    Sb 51 833.5 1592.0 2441.1 3193.7 5403.2 10420.4                          
    Te 52 869.3 1794.6 2991.0 3666.4 5789.1 6946.9 13218.5                        
    I 53 1008.7 1841.9 0.0         16402.5                      
    Xe 54 1170.1 2045.5 3097.2                                
    Cs 55 375.6 2421.8 0.0                                
    Ba 56 502.7 964.9 0.0                                
    La 57 538.1 1067.1 1850.3 4819.4                              
    Ce 58 527.4 1046.9 1948.8 3546.6                              
    Pr 59 523.1 1017.9 2086.4 3761.0 5550.8                            
    Nd 60 529.6 1035.3 2132.3 3899.0 5789.1                            
    Pm 61 535.9 1051.7 2151.6 3965.5 5952.2                            
    Sm 62 543.3 1068.1 2257.8 3994.5 6045.8                            
    Eu 63 546.7 1084.6 2404.4 4110.3 6100.8                            
    Gd 64 592.5 1166.5 1990.5 4245.4 6248.4                            
    Tb 65 564.6 1111.5 2114.0 3839.2 6412.4                            
    Dy 66 571.9 1126.0 2199.9 4001.2 5989.8                            
    Ho 67 580.6 1138.5 2203.7 4100.6 6168.3                            
    Er 68 588.7 1151.1 2194.1 4115.1 6281.2                            
    Tm 69 596.7 1162.6 2284.8 4119.0 6312.1                            
    Yb 70 603.4 1175.6 2415.0 4220.3 6327.5                            
    Lu 71 523.5 1341.1 2022.3 4360.2 6444.3                            
    Hf 72 641.6 1437.6 2248.1 3215.9 6595.4                            
    Ta 73 760.3       4657.6                            
    W 74 770.0                                    
    Re 75 759.3                                    
    Os 76 839.4                                    
    Ir 77 868.4                                    
    Pt 78 868.4 1790.8                                  
    Au 79 889.6 1977.9                                  
    Hg 80 1006.3 1809.2 3299.8                                
    Tl 81 589.1 1970.2 2875.3 4891.8                              
    Pb 82 715.4 1450.0 3080.8 4082.3 6638.2                            
    Bi 83 703.1 1609.4 2466.2 4370.8 5403.2 8519.7                          
    Po 84 813.4                                    
    Rn 86 1036.8                                    
    Fr 87 393.0                                    
    Ra 88 509.2 978.7                                  
    Ac 89 498.8 1167.5                                  
    Th 90 586.6                                    
    Pa 91 568.3                                    
    U 92 583.7                                    
    Np 93 597.2                                    
    Pu 94 584.7                                    
    Am 95 578.2                                    
    Cm 96 580.8                                    
    Bk 97 601.1                                    
    Cf 98 607.9                                    
    Es 99 619.4                                    
    Fm 100 627.2                                    
    Md 101 634.9                                    
    No 102 641.6                                    
    Lr 103 478.6                                    

    C. E. Moore, Ionization Potentials and Limits Derived from the Analyses of Optical Spectra, NSRDS-NBS 34, National Bureau of Standards, Washington, DC, 1970.
    For elements 57-72, values were obtained from Martin, W. C.; Hagan, Lucy; Reader, Joseph; Sugar, Jack J. Phys. Chem. Ref. Data, 1974, 3, 771-779.
    For elements 59-73, fifth IEs came from Sugar, Jack J. Opt. Soc. Am. 1975, 65, 1366-1367.
    For Lr see C&EN, Volume 93 Issue 15 | p. 8 | News of The Week, Issue Date: April 13, 2015 | Web Date: April 9, 2015 Lawrencium Ionization Energy Measured.
    *Values for La, Hf, and Lr have been overwritten with more recent data

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