Triple-bond compounds electronic structure

When any substituent is introduced in hydrocarbon molecules to saturate double bond or triple bond, the electronic structure of molecule will be changed, thus the thermal effect of electron transfer of 1 mol atom will have some change. According to the impact of change in molecule structure, the explosion heat of explosive can be calculated based on the corresponding corrected thermochemical data of some groups and the corrected data are listed in Table 3.9. The combustion heat of CaHi,OcN compounds under constant pressure can be calculated as the following equation ... 

The thin control of the energetic characteristics and the electronic transition nature may be carried out by chemical structure alteration. For example the appearance of CH2 group between phenyl ring and triple bond (compounds 3 and 5 in Table 4) interrupts the interaction between it-ekctrons of the both elements. This leads to the short wavelength shift in the absorption and photoconductivity spectra. The insertion of the ethynyl group instead of a CH2 group restores the conjugation. The increase in the numbers and sizes of the... 

Acetylene (C2H2) has a triple bond. Its Lewis structure shows three pairs of electrons between the carbon atoms to give them octets. The following examples show organic compounds with triple bonds. A triple dash (=) symbolizes a triple bond. 

Much earlier information on the structure of diazonium ions than that derived from X-ray analyses (but still useful today) was obtained by infrared spectroscopy. The pioneers in the application of this technique to diazonium and diazo compounds were Le Fevre and his school, who provided the first IR evidence for the triple bonds by identifying the characteristic stretching vibration band at 2260 cm-1 (Aroney et al., 1955 see also Whetsel et al., 1956). Its frequency lies between the Raman frequency of dinitrogen (2330 cm-1, Schrotter, 1970) and the stretching vibration frequency of the C = N group in benzonitrile (2255 cm-1, Aroney et al., 1955). In substituted benzenediazonium salts the frequency of the NN stretching vibration follows Hammett op relationships. Electron donor substituents reduce the frequency, whereas acceptor substituents increase it. The 4-dimethylamino group, for example, shifts it by 103 cm-1 to 2177 cm-1 (Nuttall et al., 1961). This result supports the hypothesis that... 

A similar structure for the iron compound would involve quadrivalent iron, which is very improbable, either bivalent or trivalent iron being expected. If NO loses an electron to iron, assuming the triple-bonded 2 structure, the resulting bivalent iron atom, with six d2sp3 bonds and six unshared 3d electrons, will also be in a l2 state, making the compound as a whole diamagnetic. 

Each line in a structural formula represents one pair of shared electrons, but atoms can share more than one pair of electrons. When two atoms share one pair of electrons, the bond is called a single bond, and the structural formula shows a single line. When two atoms share four electrons, the bond is called a double bond, and the structural formula shows two lines between the atoms. Similarly, when two atoms share six electrons, the bond is called a triple bond, and the stmctural formula shows three lines between the atoms. Two carbon atoms can bond to each other through any of these three kinds of bonds, as the compounds in Figure illustrate. 

For compounds (2) and (3) there is no reason to question the assignment of triple bonds and a double bond, respectively. The structure of the Cr compound of type (2) has been shown in Fig. 1. The structure of (3) is shown in Fig. 4(a). Such bonds are consistent with the attainment of 18-electron configurations. 

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