What do you mean by quadrupole moment?

The quadrupole moment of a nucleus is usually defined1 as “the quantity (3z2 — r2)Av, where the average is taken over the nuclear charges for the state which has the maximum component of spin I in the z direction”.

What is a quadrupole moment NMR?

A quadrupolar nucleus is one that has a quantum spin number greater than ½. Such nuclei have a lower symmetry than spin-½ nuclei. The quadrupole moment that varies between nuclei is a measure of this asymmetry. Their energies split upon the application of a magnetic field into multiple levels (fig. 1).

How do you calculate quadrupole moment?

Consider the system of charges shown in Figure III. 13. It has no net charge and no net dipole moment.

What is the unit of quadrupole moment?

atomic unit of electric quadrupole moment
Numerical value	4.486 551 5246 x 10-40 C m2
Standard uncertainty	0.000 000 0014 x 10-40 C m2
Relative standard uncertainty	3.0 x 10-10
Concise form	4.486 551 5246(14) x 10-40 C m2

What is quadrupole moment in NQR spectroscopy?

Nuclear quadrupole resonance spectroscopy or NQR is a chemical analysis technique related to nuclear magnetic resonance (NMR). A particular NQR frequency in a compound or crystal is proportional to the product of the nuclear quadrupole moment, a property of the nucleus, and the EFG in the neighborhood of the nucleus.

What is meant by the quadrupole moment of a Nucleous What information do you get from it about the charge distribution of nucleus?

The nuclear electric quadrupole moment is a parameter which describes the effective shape of the ellipsoid of nuclear charge distribution. The quantity Q0 is the classical form of the calculation represents the departure from spherical symmetry in the rest frame of the nucleus. …

What is the meaning of electric quadrupole?

[i¦lek·trik ′kwä·drə‚pōl] (electricity) A charge distribution that produces an electric field equivalent to that produced by two electric dipoles whose dipole moments have the same magnitude but point in opposite directions and which are separated from each other by a small distance.

What is quadrupole co2?

The most satisfactory value of a a8-a1 is taken to be 2.2 x 10-24cm3, giving for the molecular quadrupole moment of CO2— 4.1 x 10 -26 e.s.u., the sign indicating that the oxygen atoms are negative with respect to the carbon atom.

What is the quadrupole moment of a single charge?

The system possesses what is known as a quadrupole moment. While a single charge is a scalar quantity, and a dipole moment is a vector quantity, the quadrupole moment is a second order symmetric tensor. The dipole moment of a system of charges is a vector with three components given by p x = ∑ Q i x i p y = ∑ Q i y i p z = ∑ Q i z i.

What is an elementary quadrupole?

An elementary quadrupole can be represented as two dipoles oriented antiparallel. One of the most common uses of the electric quadrupole is in the characterization of nuclei. The nucleus has charge, but not dipole moment since it is all positive. But if the nucleus is not spherically symmetric, it will have a quadrupole moment.

How many components does the quadrupole moment tensor have?

The quadrupole moment tensor Q is a rank-two tensor – 3×3 matrix – and is traceless (i.e. Q x x + Q y y + Q z z = 0 {\\displaystyle Q_{xx}+Q_{yy}+Q_{zz}=0} ). The quadrupole moment tensor has thus 9 components, but because of the symmetry and zero-trace property, only 5 of these are independent.

What is the nuclear quadrupole moment if the spin is zero?

If the nuclear spin is less than or equal to 1 2 ℏ, the nuclear quadrupole moment will be zero. If the environment surrounding the nucleus possesses cubic symmetry, the electric field gradient at the nucleus is zero.