**3.1.5. Thermal ionization mass spectroscopy**

atoms) and excitation of sample in elemental analysis. ICP denotes the technique that uses

excitation of sample. This plasma is a highly energetic media consisting of inert ionized gas with equivalent temperatures from 7000 to 10,000 K. Inductively coupled plasma are formed by coupling energy produced by RF generator (typically 700–1500 W) to the plasma support gas with an electromagnetic fields [45]. The cross-section of typical ICP torch is shown in **Fig.**

Load Coil

The treatment of sample before the quantification includes vaporization, atomization,

**i. Inductively coupled plasma atomic emission spectroscopy** (ICP-AES): the method

**ii. Inductively coupled plasma atomic fluorescence spectroscopy** (ICP-AFS): ASF is an

**iii. Inductively coupled plasma-mass spectroscopy** (ICP-MS): is analytical technique for

Although there are many types of plasma, such as direct current, microwave induced, etc., the ICP is considered the

<sup>8</sup> Each element has characteristics first and second ionization potential, which depends on specific electronic structure of given element. Higher ionization potential means that more externally applied energy is required for ionization (thermal

radiation, collision with other ion or electron, or exposure to high-energy photons) [45].

analytical technique for the determination of elements in small quantities. It is based on the emission of free atoms when the excitation is performed by radiation energy.

the determination of elemental composition of virtually any material. A sample, usually in the form of an aqueous solution, is converted to an aerosol by a neutrali‐ zation process and transported to the plasma by an argon gas stream. In the plasma, the elements of analyte are atomized, followed immediately by ionization. The composition of ion population in the plasma is proportional to the concentration of

connects atomic emission spectrometry with ICP. AES is based on spontaneous emission of free atoms or ions when the excitation is performed by thermal or electric energy. The method can identify and determine the concentration of up to 40 elements simultaneously with the detection limit of parts per billion (ppb). Serious limita‐ tions of this technique are the spectral interferences. Despite rapid growth of ICP-MS, ICP-AES still plays a dominant role in elemental analysis of geological, environmen‐

Torch

The introduction of analyzed sample into inductively coupled

(ICP) for the atomization and

atmospheric pressure argon inductively coupled plasma7

116 Apatites and their Synthetic Analogues - Synthesis, Structure, Properties and Applications

Plasma

**Fig. 2.** Plasma with torch assembly and load coil [45].

tal, biological and other materials.

most useful technique for analytical spectroscopy [45].

excitation and ionization.8

Ground

plasma was applied in analytical techniques including [29],[45],[46],[47],[48]:

**2**.

7

Thermal ionization mass spectroscopy (TIMS) is highly specialized technique of mass spectroscopy used for very precise determination of isotope ratios and, as such, is widely used for the determination of stable isotope ratios in isotope geology and for the analysis of nuclear materials [58]. In this method, the solid sample is thermally ionized in solid-source mass spectrometer. Ions are accelerated into the mass analyzer and then transported to the detec‐ tor [59]. Multicollector thermal ionization mass spectrometry (MC-TIMS) uses laminated magnetic sector filet for high speed peak jumping and low hysteresis for the mass of ion beams [60],[61].

The basic variants of the method of thermal ionization mass spectroscopy are as follows:


The ability for precise determination of isotope ratio in apatite predetermines this method for geochronological investigations, i.e. studying of chronologic records in accessory minerals of igneous rocks [61],[63],[64],[65].
