Phosphorus electronegativity

Phosphorus trifluoride is a colourless gas the molecule has a shape similar to that of phosphine. Although it would not be expected to be an electron donor at all (since the electronegative... 

Table 4. Properties and Electronegativity Differences of Phosphorus—Atom Bonds ...

PI ace the following elements in order of increasing electronegativity oxygen, carbon, nitrogen, fluorine, silicon, phosphorus, sulfur. 

State which atom of each of the following pairs is more electronegative (a) sulfur, phosphorus (b) selenium, tellurium (c) sodium, cesium (d) silicon, oxygen. 

Phosphorus and arsenic have nearly identical electronegativities, so in GaP Asi. , the dominant effect is the smaller atomic radius of P relative to As. Substituting P atoms for As atoms shrinks the dimensions of the semiconductor lattice. This leads to greater overlap of the valence orbitals, increased stability of the bonding orbitals (valence band), and an increased band gap. 

The chemical shifts for P—F compounds have been reviewed.The compounds differ from most other organophosphorus compounds because Sp becomes more positive as the electronegativity of the atoms attached to phosphorus increases. The effect is at a maximum for P" compounds. They behave normally with regard to an increase in shielding with increase in co-ordination number and therefore the P" compounds are the least shielded. Thus the largest negative values (— 190 to — 250) are observed for compounds of the type YPFj. With the new value of Sp of + 80 for PFg, the variation of Sp with the number of fluorine atoms in P compounds is now shown to be fairly consistent. The value of Sp has also been reported for a series of aminohalogeno P compounds. -... 

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