MIR AND FIR ANALYSIS OF INORGANIC SPECIES IN A SINGLE DATA ACQUISITION
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2017-06-19 |
| Authors | Peng Wang, ĐĄ. Đ. ШиНОв |
| Institutions | Bruker (United States) |
| Analysis | Full AI Review Included |
Technical Documentation & Driver: MPCVD Diamond for Extended-Range FTIR Spectroscopy
Section titled âTechnical Documentation & Driver: MPCVD Diamond for Extended-Range FTIR SpectroscopyâExecutive Summary
Section titled âExecutive SummaryâThe reported research successfully demonstrates the extension of FTIR spectral analysis into the Far-Infrared (FIR) and Terahertz (THz) ranges in a single data acquisition scan, a critical advancement for low-energy vibrational analysis in materials science, geology, and pharmaceutical research.
- Achieved wide-range Mid-Infrared (MIR) and Far-Infrared (FIR) analysis in a single scan, overcoming historical spectral bottlenecks.
- Extended routine spectral coverage from 6000 cm-1 down to 50 cm-1 using optimized components, including the standard SiC source.
- The key enabling technology is the integration of a wide-range DLaTGS detector featuring a robust, broadband diamond window.
- Ultra-low energy vibrational modes (lattice and intermolecular) are proven accessible, with the range ultimately extending down to 10 cm-1 (0.3 THz) using high-power external sources.
- Applications include the identification of inorganic species, analysis of pigments, additives in polymers, and crucial polymorphism screening.
- This breakthrough eliminates the need for multiple beam splitters and detector exchanges previously required to cover the FIR/THz gap.
Technical Specifications
Section titled âTechnical SpecificationsâThe following parameters define the performance and system architecture detailed in the research for extended-range MIR-FIR analysis.
| Parameter | Value | Unit | Context |
|---|---|---|---|
| Standard Single Scan Spectral Range | 6000 to 50 | cm-1 | Achieved using standard SiC source, MIR-FIR beam splitter, and diamond window DLaTGS detector. |
| Extended Spectral Range (Maximum) | Down to 10 | cm-1 | Achieved using external water-cooled mercury arc high-power lamp. |
| Standard Source Type | SiC IR Source | N/A | Used for primary 6000 to 50 cm-1 measurements. |
| High Power Source Type | Water cooled mercury arc lamp | N/A | Used for ultimate extension down to 10 cm-1. |
| Standard Globar Source Coverage | 8000 to 20 | cm-1 | Broadest conventional source range, but typically limited by existing beam splitter/detector configuration. |
| Critical Component | Diamond Window | N/A | Utilized by the DLaTGS detector to enable wide-range spectral coverage (MIR to FIR/THz). |
| Measurement Modes Supported | Transmittance, Reflectance, ATR | N/A | All standard FTIR analysis modes are supported across the extended range. |
Key Methodologies
Section titled âKey MethodologiesâThe successful extension of FTIR capability relies on specific optical system component upgrades that leverage the unique properties of diamond in the infrared spectrum.
- Component Integration: Incorporation of two key optical components into the FTIR system: a specialized wide-range MIR-FIR beam splitter and a DLaTGS detector utilizing a high-transparency CVD diamond window.
- Broadband Detection: The use of the CVD diamond window is essential, providing high transparency and ruggedness across the extended MIR (4000 to 400 cm-1), FIR (400 to 10 cm-1), and THz regions.
- Standard Source Configuration: Utilization of a standard SiC IR source coupled with the new optical components to achieve effective broadband spectral coverage from 6000 to 50 cm-1 in a single data acquisition scan.
- Extreme FIR/THz Extension: Employing an external, water-cooled mercury arc high-power lamp to increase signal strength and push the spectral analysis limit further, enabling robust measurements down to 10 cm-1.
- Material Analysis: Conducting the extended-range measurements (transmittance, reflectance, ATR) to observe low energy vibrational modes (intermolecular and lattice vibrations) critical for characterizing polymorphism and complex solid-state structures.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & Capabilitiesâ6CCVD provides the specialized, high-purity MPCVD diamond materials necessary to replicate and advance the technology described in this research, specifically targeting demanding optical and THz window applications.
Applicable Materials
Section titled âApplicable MaterialsâThe technical requirements demand a material with exceptional optical transparency, thermal conductivity, and mechanical robustness across the MIR and FIR/THz ranges.
| Requirement/Goal | 6CCVD Material Solution | Rationale for Selection |
|---|---|---|
| High-Purity Detector Window (e.g., DLaTGS) | Optical Grade Single Crystal Diamond (SCD) | SCD offers superior purity (low nitrogen), ensuring minimal absorption and scatter across the entire spectral range (6000 to 10 cm-1), critical for high-sensitivity FIR/THz detectors. |
| High-Durability ATR Element | High-Purity Polycrystalline Diamond (PCD) | Diamondâs unmatched hardness provides superior resistance to scratching and chemical erosion during demanding ATR measurements of hard or corrosive samples. |
| THz/FIR Optical Substrates | Thin SCD or Low-Loss PCD | CVD diamondâs extremely high thermal conductivity minimizes thermal lensing effects when using high-power external sources (like the mercury arc lamp). |
| Custom Electronic/Thermal Management | Boron-Doped Diamond (BDD) | For detectors or components requiring integrated heating elements or specific conductivity, BDD offers controllable electrical properties while maintaining high strength. |
Customization Potential
Section titled âCustomization Potentialâ6CCVDâs advanced MPCVD growth and processing capabilities are perfectly aligned to support the manufacturing of custom optical components for advanced spectroscopy systems.
- Custom Dimensions: We supply optical plates and wafers in custom shapes and dimensions, up to 125mm (PCD), ensuring seamless integration into specialized spectrometer architectures (e.g., detector enclosures or beam paths).
- Precision Polishing: Achieving high surface quality is paramount for minimizing signal scatter in the FIR/THz range. We offer optical polishing specifications down to Ra < 1 nm (SCD), guaranteeing maximum throughput and spectral fidelity.
- Thickness Control: We provide materials in thicknesses ranging from 0.1 Âľm to 500 Âľm (SCD/PCD), allowing engineers to specify ideal thickness for anti-reflection optimization or mechanical constraints of the window element.
- Advanced Metalization: Should the detector window require specific mounting interfaces, electrode patterns, or anti-reflective coatings, 6CCVD offers in-house custom metalization services (e.g., Ti/Pt/Au, W, Cu, Pd).
Engineering Support
Section titled âEngineering Supportâ6CCVDâs in-house PhD team specializes in optimizing MPCVD diamond parameters for demanding optical and thermal applications. We offer authoritative assistance with:
- Material selection for similar FTIR, THz imaging, and ATR spectroscopy projects requiring superior mechanical, thermal, and optical properties.
- Designing crystal orientation and doping levels to achieve specific thermal dissipation or electrical conductivity targets when integrating diamond into complex detector assemblies.
- Consultation on optical polishing requirements and geometry specifications to maximize beam uniformity and minimize interference effects across ultra-wide spectral ranges.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly. Global shipping is available (DDU default, DDP available).
View Original Abstract
The extension of the mid IR towards the far IR spectral range below 400 wn is of great interest for molecular vibrational analysis for inorganic and organometallic chemistry, for geological, pharmaceutical, and physical applications, polymorph screening and crystallinity analysis as well as for matrix isolation spectroscopy. In these cases, the additional far infrared region offers insight to low energy vibrations which are observable only there. This includes inorganic species, lattice vibrations or intermolecular vibrations in the ordered solid state.x000d\n\tThe spectral range of a FTIR spectrometer is defined by the major optical components such as the source, beamsplitter, and detector. The globar source covers a broad spectral range from 8000 to 20 wn. However a bottle neck exists with respect to the beamsplitter and detector. To extend the spectral range further into the far IR and THz spectral ranges, one or more additional far IR beam splitters and detectors have been previously required. \tTwo new optic components have been incorporated in a spectrometer to achieve coverage of both the mid and far infrared in a single scan: a wide range MIR-FIR beam splitter and the wide range DLaTGS detector that utilizes a diamond window. The use of a standard SiC IR source with these components yields a spectral range of 6000 down to 50 wn in one step for all types of transmittance, reflectance and ATR measurements. Utilizing the external water cooled mercury arc high power lamp the spectral range can be ultimately extended down to 10 wn. Examples of application will include emission in MIR-THz range, identification of pigments, additives in polymers, and polymorphism studies.x000d