# 23. Quantum Chemical descriptors

## Definition

## Relevant descriptors

Quantum chemical descriptors are obtained from quantum-chemical calculations. The energy level E_{i}
and wave function Ψ_{i} are computed by solving the schrodinger equation. This depends on the molecular properties which is
calculated from quantum chemistry and directly deals with molecular electron density and electron distribution function.

No. | Descriptor |

1 | No. of occupied electronic levels |

2 | No. of occupied electronic levels / # of atoms |

3 | HOMO-1 energy |

4 | HOMO energy |

5 | LUMO energy |

6 | LUMO+1 energy |

7 | HOMO - LUMO energy gap |

8 | min nucleophilic reactivity index (S) |

9 | max nucleophilic reactivity index (S) |

10 | avg nucleophilic reactivity index (S) |

11 | min nucleophilic reactivity index (N) |

12 | max nucleophilic reactivity index (N) |

13 | avg nucleophilic reactivity index (N) |

14 | min nucleophilic reactivity index (C) |

15 | max nucleophilic reactivity index (C) |

16 | avg nucleophilic reactivity index (C) |

17 | min nucleophilic reactivity index (O) |

18 | max nucleophilic reactivity index (O) |

19 | avg nucleophilic reactivity index (O) |

20 | min electrophilic reactivity index (S) |

21 | max electrophilic reactivity index (S) |

22 | avg electrophilic reactivity index (S) |

23 | min electrophilic reactivity index (N) |

24 | max electrophilic reactivity index (N) |

25 | avg electrophilic reactivity index (N) |

26 | min electrophilic reactivity index (C) |

27 | max electrophilic reactivity index (C) |

28 | avg electrophilic reactivity index (C) |

29 | min electrophilic reactivity index (O) |

30 | max electrophilic reactivity index (O) |

31 | avg electrophilic reactivity index (O) |

32 | min 1-electron reactivity index (S) |

33 | max 1-electron reactivity index (S) |

34 | avg 1-electron reactivity index (S) |

35 | min 1-electron reactivity index (N) |

36 | max 1-electron reactivity index (N) |

37 | avg 1-electron reactivity index (N) |

38 | min 1-electron reactivity index (C) |

39 | max 1-electron reactivity index (C) |

40 | avg 1-electron reactivity index (C) |

41 | min 1-electron reactivity index (O) |

42 | max 1-electron reactivity index (O) |

43 | avg 1-electron reactivity index (O) |

44 | max net atomic charge (S) |

45 | min net atomic charge (S) |

46 | max net atomic charge (N) |

47 | min net atomic charge (N) |

48 | max net atomic charge (C) |

49 | min net atomic charge (C) |

50 | max net atomic charge (O) |

51 | min net atomic charge (O) |

52 | max net atomic charge (H) |

53 | min net atomic charge (H) |

54 | max net atomic charge |

55 | min net atomic charge |

56 | total molecular dipole |

57 | total point charge comp. (molecular dipole) |

58 | total hybridization comp. (molecular dipole) |

59 | Image of the Onsager-Kirkwood solvation energy |

60 | TMSA [QC] |

61 | PPSA-1 [QC] |

62 | PNSA-1 [QC] |

63 | DPSA-1 [QC] |

64 | FPSA-1 [QC] |

65 | FNSA-1 [QC] |

66 | WPSA-1 [QC] |

67 | WNSA-1 [QC] |

68 | PPSA-2 [QC] |

69 | PNSA-2 [QC] |

70 | DPSA-2 [QC] |

71 | FPSA-2 [QC] |

72 | FNSA-2 [QC] |

73 | WPSA-2 [QC] |

74 | WNSA-2 [QC] |

75 | PPSA-3 [QC] |

76 | PNSA-3 [QC] |

77 | DPSA-3 [QC] |

78 | FPSA-3 [QC] |

79 | FNSA-3 [QC] |

80 | WPSA-3 [QC] |

81 | WNSA-3 [QC] |

82 | RPCG (most positive charge / total positive charge) [QC] |

83 | RPCS (most positive surface area * RPCG) [QC] |

84 | RNCG (most negative charge / total positive charge) [QC] |

85 | RNCS (most negative surface area * RNCG) [QC] |

86 | HDSA [QC] |

87 | HFHDSA (HDSA/TMSA) [QC] |

88 | HASA [QC] |

89 | FHASA (HASA/TMSA) [QC] |

90 | HBSA [QC] |

91 | FHBSA (HBSA/TMSA) [QC] |

92 | HDCA [QC] |

93 | FHDCA (HDCA/TMSA) [QC] |

94 | HACA [QC] |

95 | FHACA (HACA/TMSA) [QC] |

96 | HBCA [QC] |

97 | FHBCA (HBCA/TMSA) [QC] |

98 | min(nHA, nHD) [QC] |

99 | count of HA sites [QC] |

100 | count of HD sites [QC] |

101 | HA dep. HDSA-1 [QC] |

102 | HA dep. HDSA-1/TMSA [QC] |

103 | HA dep. HDSA-2 [QC] |

104 | HA dep. HDSA-2/TMSA [QC] |

105 | HA dep. HDSA-2/sqrt(TMSA) [QC] |

106 | HA dep. HDCA-1 [QC] |

107 | HA dep. HDCA-1/TMSA [QC] |

108 | HA dep. HDCA-2 [QC] |

109 | HA dep. HDCA-2/TMSA [QC] |

110 | HA dep. HDCA-2/sqrt(TMSA) [QC] |

111 | HASA-1 [QC] |

112 | HASA-1/TMSA [QC] |

113 | HASA-2 [QC] |

114 | HASA-2/TMSA [QC] |

115 | HASA-2/sqrt(TMSA) [QC] |

116 | HACA-1 [QC] |

117 | HACA-1/TMSA [QC] |

118 | HACA-2 [QC] |

119 | HACA-2/TMSA [QC] |

120 | HACA-2/sqrt(TMSA) [QC] |

121 | min AO electronic populaiton |

122 | max AO electronic population |

123 | max bond order (sigma-sigma) |

124 | max bond order (pi-pi) |

125 | max bond order (sigma-pi) |

126 | min valency (S) |

127 | max valency (S) |

128 | avg valency (S) |

129 | min (>0.1) bond order (S) |

130 | max bond order (S) |

131 | avg bond order (S) |

132 | min valency (N) |

133 | max valency (N) |

134 | avg valency (N) |

135 | min (>0.1) bond order (N) |

136 | max bond order (N) |

137 | avg bond order (N) |

138 | min valency (C) |

139 | max valency (C) |

140 | avg valency (C) |

141 | min (>0.1) bond order (C) |

142 | max bond order (C) |

143 | avg bond order (C) |

144 | min valency (O) |

145 | max valency (O) |

146 | avg valency (O) |

147 | min (>0.1) bond order (O) |

148 | max bond order (O) |

149 | avg bond order (O) |

150 | min valency (H) |

151 | max valency (H) |

152 | avg valency (H) |

153 | min (>0.1) bond order (H) |

154 | max bond order (H) |

155 | avg bond order (H) |