Related Experiment Video
Updated: Jun 13, 2026
06:57
Theoretical Calculation and Experimental Verification for Dislocation Reduction in Germanium Epitaxial Layers with Semicylindrical Voids on Silicon
Published on: July 17, 2020
Resolving the germanium atomic weight disparity using multicollector ICPMS
1Institute for National Measurement Standards, National Research Council Canada, Ottawa, Ontario, Canada, K1A 0R6. lu.yang@nrc-cnrc.gc.ca
Analytical Chemistry
|April 29, 2010
Summary
New mass spectrometry measurements determined the atomic weight of germanium to be 72.6296(19). This result supports the 2009 Standard Atomic Weight adjustment for germanium isotopes.
Area of Science:
- Geochemistry
- Analytical Chemistry
- Nuclear Physics
Background:
- Previous measurements of germanium's atomic weight using different mass spectrometry techniques yielded conflicting results.
- Discrepancies in atomic weight values necessitate precise redetermination for accurate scientific application.
Purpose of the Study:
- To accurately determine the atomic weight of germanium using multicollector inductively coupled plasma mass spectrometry.
- To provide reliable data supporting the International Union of Pure and Applied Chemistry (IUPAC) 2009 Standard Atomic Weight adjustment.
Main Methods:
- Utilized multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) for high-precision isotope ratio measurements.
- Employed a regression mass bias correction model calibrated with NIST SRM 994 gallium isotopic reference material.
- Calculated germanium isotope ratios without assumptions on mass bias differences between gallium and germanium isotopes.
Main Results:
- Determined the atomic weight of germanium to be 72.6296(19) (k=2).
- Obtained precise isotope ratios: n(70Ge)/n(74Ge) = 0.5620(21), n(72Ge)/n(74Ge) = 0.7515(16), n(73Ge)/n(74Ge) = 0.2125(7), and n(76Ge)/n(74Ge) = 0.2121(12).
- Results align with and support the upcoming 2009 IUPAC Standard Atomic Weight adjustment.
Conclusions:
- The MC-ICP-MS measurement provides a precise and reliable atomic weight for germanium.
- The findings contribute to the ongoing standardization of atomic weights by IUPAC.
- This study resolves previous discrepancies and establishes a new reference value for germanium's atomic weight.
Related Concept Videos
01:20Inductively Coupled Plasma-Mass Spectrometry (ICP-MS): Interferences
Inductively coupled plasma–mass spectrometry (ICP–MS) is a highly selective and sensitive technique for accurate elemental analysis. Though the analysis of ICP–MS mass spectra is comparatively straightforward, it is affected by spectroscopic and non-spectroscopic interferences. Spectroscopic interferences arise when the plasma contains ionic species with an m/z value the same as the analyte ion. Spectroscopic interference can be categorized as isobaric, polyatomic ions, and refractory oxide ion...
01:19Inductively Coupled Plasma–Mass Spectrometry (ICP–MS): Overview
In inductively coupled plasma–mass spectrometry (ICP–MS), an inductively coupled plasma (ICP) torch is used as an atomizer and ionizer. Solid samples are dissolved and volatilized before being introduced into the high-temperature argon plasma, while solution samples are nebulized and passed through the high-temperature argon plasma. Plasma dissociates the analytes and ionizes their component atoms to form a mixture of positive ions and molecular species. The positive ions are then passed on to...
01:19Inductively Coupled Plasma Atomic Emission Spectroscopy: Principle
Inductively coupled plasma (ICP) is the most widely used plasma source in atomic emission spectroscopy (AES), also known as Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). The ICP source, or torch, consists of three concentric quartz tubes with argon gas flowing through them. A spark from a Tesla coil initiates the ionization of argon, generating a high-temperature plasma.
The ions and electrons produced interact with the fluctuating magnetic field created by a water-cooled...
The ions and electrons produced interact with the fluctuating magnetic field created by a water-cooled...
01:03Precipitation Gravimetry
Precipitation gravimetry is based on converting an analyte into a sparingly soluble precipitate, which is separated by filtration and weighed. An ideal precipitate should be pure, insoluble, of known composition, and easily filtered from the reaction mixture.
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...
01:29Atomic Emission Spectroscopy: Lab
AES is a powerful analytical technique, especially effective when used with plasma sources, producing abundant spectra in characteristic emission lines. The Inductively Coupled Plasma (ICP), in particular, yields superior quantitative analytical data due to its high stability, low noise, low background, and minimal interferences under optimal experimental conditions. However, newer air-operated microwave sources are emerging as promising alternatives that could be more cost-effective than...
01:15High-Resolution Mass Spectrometry (HRMS)
The resolution of a mass spectrometer depends on the efficiency of separating ions with different ion masses. The mass of an atom is approximated to the sum of the masses of protons and neutrons inside, considering the masses of protons and neutrons as equal. However, the masses of the proton (1.6726 × 10−24 g) and neutron (1.6749 × 10−24 g) are not truly equal. There is a minor error in the expression of atomic masses relative to the simplest atom of hydrogen. For example, the mass of helium...