Related Experiment Video
Updated: Jul 12, 2026
10:44
Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Carbynes in meteorites: detection, low-temperature origin, and implications for interstellar molecules
Science (New York, N.Y.)
|September 26, 1980
Summary
Allende meteorite carbon is carbyne, not graphite. This triply bonded carbon forms at low temperatures via catalysis, suggesting it
Area of Science:
- * Cosmochemistry and materials science, focusing on carbon allotropes.
Background:
- * Carbonaceous meteorites contain unique carbon structures.
- * Carbyne, a form of elemental carbon with triple bonds, was previously thought to form only under extreme conditions (high temperature or pressure).
Purpose of the Study:
- * To identify the specific allotrope of carbon present in the Allende meteorite.
- * To investigate novel, low-temperature formation pathways for carbyne.
Main Methods:
- * Thermal analysis of Allende meteorite carbon samples (heating between 250-330°C).
- * Analysis of reaction products, including triply bonded carbon fragments and cyanopolyacetylenes.
- * Experimental investigation of carbyne formation via catalytic reaction of carbon monoxide (CO) at 300-400°C using a chromite catalyst.
Main Results:
- * Heating Allende meteorite carbon released triply bonded fragments, confirming its carbyne nature.
- * Carbyne was synthesized metastably at low temperatures (300-400°C) through a catalytic reaction: 2CO → CO2 + C.
- * The formation of carbyne via surface catalysis is proposed as a significant source in terrestrial, meteoritic, and interstellar environments.
Conclusions:
- * The carbon in the Allende meteorite is identified as carbyne.
- * Low-temperature catalytic surface reactions provide a plausible mechanism for carbyne formation, challenging previous high-energy requirements.
- * This discovery has implications for understanding the origin and abundance of carbyne and related compounds in space and on Earth.
Related Concept Videos
01:27Atomic Spectroscopy: Effects of Temperature
Atomization, converting samples into gas-phase atoms and ions, is essential for atomic spectroscopy. The flame temperature required for atomization affects the efficiency of the atomic spectroscopic methods by increasing the atomization efficiency and the relative population of the excited and ground states.
At thermal equilibrium, the relative populations of excited and ground state atoms can be estimated using the Maxwell–Boltzmann distribution. For example, an increase in temperature from...
At thermal equilibrium, the relative populations of excited and ground state atoms can be estimated using the Maxwell–Boltzmann distribution. For example, an increase in temperature from...
01:15¹H NMR of Conformationally Flexible Molecules: Variable-Temperature NMR
The axial and equatorial protons in cyclohexane can be distinguished by performing a variable-temperature NMR experiment. In this process, except for one proton, the remaining eleven protons are replaced by deuterium. The deuterium substitution avoids the possible peak splitting caused by the spin-spin coupling between the adjacent protons. The remaining proton flips between the axial and equatorial positions.
02:06Conditions on Early Earth
Around 4 billion years ago, oceans began to condense on earth while volcanic eruptions released nitrogen, carbon dioxide, methane, ammonia, and hydrogen into the primordial atmosphere. However, organisms with the characteristics of life were not initially present on earth. Scientists have used experimentation to determine how organisms evolved that could grow, reproduce, and maintain an internal environment.
02:06Conditions on Early Earth
Around 4 billion years ago, oceans began to condense on earth while volcanic eruptions released nitrogen, carbon dioxide, methane, ammonia, and hydrogen into the primordial atmosphere. However, organisms with the characteristics of life were not initially present on earth. Scientists have used experimentation to determine how organisms evolved that could grow, reproduce, and maintain an internal environment.
01:26Spectroscopy of Carboxylic Acid Derivatives
Infrared spectroscopy is primarily used to determine the types of bonds and functional groups. In carboxylic acid derivatives, a typical carbonyl bond absorption is observed around 1650–1850 cm−1. For esters, the absorption is recorded at around 1740 cm−1, while acid halides show the absorption at about 1800 cm−1. Another acid derivative, the acid anhydrides, exhibit two carbonyl absorption around 1760 cm−1 and 1820 cm−1, arising from the symmetrical and unsymmetrical carbonyl vibration.
In the...
In the...
02:10Carbocations
Carbocations are one of the reaction intermediates formed during several nucleophilic substitutions or elimination reactions. A carbocation is an electron-deficient species with the central carbon atom having six electrons and three bonded atoms. The central carbon in a carbocation is sp2 hybridized with trigonal planar geometry. It has an empty p orbital perpendicular to the plane of the structure that can accept electrons. Thus, carbocations act as strong electrophiles and may react with any...